This document describes the changes made to the ERTS application.
Fix bug in tracing with matchspec body containing
Own Id: OTP-9422 Aux Id: seq11868
Fix emulator deadlock in
Own Id: OTP-9423 Aux Id: seq11872
The
Own Id: OTP-9339 Aux Id: Seq11780
Fix binary and iolist overflow problems. Typically problems arose in length calculation where the result would exceed (1 bsl 32 - 1).
Own Id: OTP-9118
Using the old erlang shell (i.e. erl instead on werl) on windows and doing several init:restart's would eventually hang the VM. That is no longer the case.
Own Id: OTP-9139
Removed recursive C code when printing Erlang terms to buffers, avoiding stack overflows that could cause VM to crash.
Own Id: OTP-9140
The send_timeout option in gen_tcp did not work properly in active mode or with {active,once} options. This is now corrected.
Own Id: OTP-9145
Fixed various typos across the documentation (Thanks to Tuncer Ayaz)
Own Id: OTP-9154
Remove duplicate stack entries which could occur after calling certain BIFs.
Own Id: OTP-9163
A race when starting two nodes simultaneously using run_erl has been removed.
Own Id: OTP-9164
Add documentation on .erlang processing back again (Thanks to Gabor Liptak)
Own Id: OTP-9189
Remove gratuitous paren in driver_entry(Thanks to Tuncer Ayaz)
Own Id: OTP-9192
Fix some wrong pointer dereferences (Thanks to Cristian Greco)
Own Id: OTP-9194
erts: Remove unused variables (Thanks to Tuncer Ayaz)
Own Id: OTP-9205
The documentation for
Own Id: OTP-9209
Allow user to specify the IP address epmd binds to
The IP address(es) epmd binds to can now be specified by the user, either via epmd's new "-address" option or (if that's not used) by setting the environment variable ERL_EPMD_ADDRESS. Multiple addresses may be specified using a comma-separated list. If the loopback address is not in this list, it will be added implicitly, so that the daemon can be queried by an interactive epmd process.(Thanks to Holger Weiß)
Own Id: OTP-9213
epmd: include host address in local access check
In FreeBSD jails, the source and destination address of connections to localhost are changed to be the IP address of the jail. Consider connections from the host's IP address to itself (e.g., the source and destination address match) to be local for the access control checks. (Thanks to Michal Santos and Tom at diogunix.com)
Own Id: OTP-9214
Fix list returned by net_kernel:epmd_module
Function epmd_module of net_kernel returns a list instead of an atom, when the epmd_module-flag is used. (Thanks to Markus Knofe)
Own Id: OTP-9215
Fix epmd's dbg_perror() output
The dbg_perror() function now hands the current errno value over to dbg_gen_printf(). This fixes the problem that errno had been reset to zero by the time it was used (to print the corresponding error message) in the dbg_gen_printf() function. (Thanks to Holger Weiß)
Own Id: OTP-9223
heart: remove garbage appended to heart command
heart:get_cmd/0 is documented to return an empty string if the command is cleared. get_cmd/0 returns 2 extra bytes: 1 byte for the trailing null, 1 byte from the op (the op is an unsigned char and 2 bytes are allocated for it in the returned buffer). (Thanks to Michael Santos)
Own Id: OTP-9224
file: fix hang reading compressed files
The gzio driver goes into an infinite loop when reading past the end of a compressed file. Reported-By: Alex Morarash (Thanks to Michael Santos)
Own Id: OTP-9245
Eliminate alias warnings from gcc 4.5.2
Own Id: OTP-9250
Unsigned integer may overflow in error message (Thanks to Michael Santos)
Own Id: OTP-9251
Driver names should be strings, not atoms
Own Id: OTP-9253
driver_entry: Remove gratuitous paren and fix typo (Thanks to Tuncer Ayaz)
Own Id: OTP-9254
Fix format specifiers in erl_exit messages
Fix an error message by using an unsigned integer specifier as seen in a tweet by @metabrew: #erlang VM crashed with "no next heap size found: -2090496108, offset 0", suddenly allocated all available RAM
Also correct mis-typed string formats in bif.c.(Thanks to Michael Santos)
Own Id: OTP-9262
net_drv: remove unused tcp request id inet_drv: remove gratuitous assignment (Thanks to Tuncer Ayaz)
Own Id: OTP-9263
Teach run_erl RUN_ERL_DISABLE_FLOWCNTRL for disabling flow control
Flow control can cause unwanted behaviour of the beam process, if accidentally hit Ctrl-S (instead of Ctrl-D to detach) the entire beam may be blocked.
Fix this problem by making it possible to turn off flow control by setting the environment variable RUN_ERL_DISABLE_FLOWCNTRL. (Thanks to Jonas Faklkevik)
Own Id: OTP-9270
The following bugs due to missing memory barriers have been fixed:
ETS tables using the
ETS tables using the
A number of memory barriers
have been added when building with the
The BIF
A thread blocking other threads during code loading, or setup of tracing could potentially read invalid data.
Fixation of ETS tables could potentially get into an internally inconsistent state.
Own Id: OTP-9281
Fix halfword bug for ETS ordered_set when doing
Own Id: OTP-9292
Fix bug in
Own Id: OTP-9298
Calling
Own Id: OTP-9302
New
Own Id: OTP-9150
A process being garbage collected by another process
could be scheduled on another scheduler. This prevented
this scheduler from doing any useful work until the
garbage collection was done. This either occurred due to
a explicit call to the
Own Id: OTP-9211
Remove unnecessary validation copy in prim_file:drv_command/3 (Thanks to Tony Rogvall)
Own Id: OTP-9276
Symbolic link handling on windows have been slightly updated to map error conditions more consequently and correctly read directory links created outside of the Erlang environment.
Own Id: OTP-9279
Due to standard library DLL mismatches between versions of OpenSSL and Erlang/OTP, OpenSSL is now linked statically to the crypto driver on Windows. This fixes problems starting crypto when running Erlang as a service on all Windows versions.
Own Id: OTP-9280
Halfword emulator memory handling improvements:
Much more of internal memory structures have been made able to use "high" memory and are no longer restricted to the 4Gb limit that still applies for all process heap data.
Fixed faulty
values from
New counter
Own Id: OTP-9291 Aux Id: seq11841
The value set in the undocumented and unsupported ERL_version_FLAGS (e.g. ERL_R14B03_FLAGS) environment variable can now be overridden by the command line (similar to ERL_AFLAGS).
Own Id: OTP-9297
Fix halfword emulator bug in
Own Id: OTP-9258 Aux Id: seq11836
Ets table type ordered_set could order large integer keys wrongly on pure 64bit platforms. This is now corrected.
Own Id: OTP-9181
The status of a process was unnecessarily set to waiting
before a process was enqueued in a run queue. This bug
was harmless up until OTP-R14B01. In OTP-R14B02
OTP-9125 also introduced a thread unsafe access to the status field of a process which now also have been fixed.
*** INCOMPATIBILITY with noxs ***
Own Id: OTP-9197
The scroll wheel now scrolls the werl window on Windows.
Own Id: OTP-8985
Some malformed distribution messages could cause VM to crash, this is now corrected.
Own Id: OTP-8993
The OS function getifaddrs() can return NULL in some address fields for e.g PPP and tunnel devices which caused the emulator to segfault. This bug has now been corrected.
Own Id: OTP-8996
The expression <<A:0>> would always produce
an empty binary, even if
Own Id: OTP-8997
A bug that potentially could cause an emulator crash when deleting an ETS-table has been fixed. A resource leak when hitting the maximum amount of ETS-tables allowed has also been fixed.
Own Id: OTP-8999
A bug in the
Own Id: OTP-9005
Due to a bug in glibc the runtime system could abort while trying to destroy a mutex. The runtime system will now issue a warning instead of aborting.
Own Id: OTP-9009
A bug in epmd could create strange behaviour when listen() calls failed. This is now corrected thanks to Steve Vinoski.
Own Id: OTP-9024
When setting file_info the win32_driver will now correctly set access and modified time. Previously these entities were swapped.
Own Id: OTP-9046
Setting scheduler bind type to
Own Id: OTP-9056 Aux Id: Seq11779
Two problems were fixed in crash dump: The time left for timers are now shown as unsigned integers and the contents of ordered_set ETS tables is no longer included.
Own Id: OTP-9057
The VM could fail to set IP_TOS and SO_PRIORITY in certain situations, either because sockets were supplied as open file descriptors, or because SO_PRIORITY by default was set higher than the user can explicitly set it to. Those situations are now handled.
Own Id: OTP-9069
Wx on MacOS X generated complains on stderr about certain cocoa functions not beeing called from the "Main thread". This is now corrected.
Own Id: OTP-9081
Fix a couple typos in driver_entry(3) (thanks to Tuncer Ayaz).
Own Id: OTP-9085
Mention that "-detached" implies "-noinput"
Clarify that specifying "-noinput" is unnecessary if the "-detached" flag is given. (thanks to Holger Weiß)
Own Id: OTP-9086
A potential problem (found by code inspection) when calling a fun whose code was not loaded has been fixed.
Own Id: OTP-9095
The emulator could get into a state where it didn't check for I/O.
Own Id: OTP-9105 Aux Id: Seq11798
Attempting to create binaries exceeding 2Gb (using for
example
Own Id: OTP-9117
Fix erlang:hibernate/3 on HiPE enabled emulator (Thanks to Paul Guyot)
Own Id: OTP-9125
From this release, the previously experimental
halfword emulator is now official. It can be enabled by
giving the
The halfword emulator is a 64-bit application, but uses halfwords (32-bit words) for all data in Erlang processes, therefore using less memory and being faster than the standard 64-bit emulator. The total size of all BEAM code and all process data for all processes is limited to 4Gb, but ETS tables and off-heap binaries are only limited by the amount of available memory.
Own Id: OTP-8941
32-bit atomic memory operations have been introduced internally in the run time system, and are now used where appropriate. There were previously only atomic memory operations of word size available. The 32-bit atomic memory operations slightly reduce memory consumption, and slightly improve performance on 64-bit runtime systems.
Own Id: OTP-8974
Performance enhancements for looking up timer-entries and removing timers from the wheel.
Own Id: OTP-8990
Write accesses to ETS tables have been optimized by reducing the amount of atomic memory operations needed during a write access.
Own Id: OTP-9000
Strange C coding in the VM made the -D_FORTIFY_SOURCE option to gcc-4.5 react badly. The code is now cleaned up so that it's accepted by gcc-4.5.
Own Id: OTP-9025
The memory footprint for loaded code has been somewhat reduced (especially in the 64-bit BEAM machine).
Own Id: OTP-9030
The maximum number of allowed arguments for an Erlang function has been lowered from 256 to 255, so that the number of arguments can now fit in a byte.
Own Id: OTP-9049
Dependency generation for Makefiles has been added to the
compiler and erlc. See the manual pages for
Own Id: OTP-9065
Fix format_man_pages so it handles all man sections and remove warnings/errors in various man pages.
Own Id: OTP-8600
The
Own Id: OTP-8847
Windows 2003 and Windows XP pre SP3 would sometimes not start the Erlang R14B VM at all due to a bug in the cpu topology detection. The bug affects Windows only, no other platform is even remotely affected. The bug is now corrected.
Own Id: OTP-8876
The HiPE run-time in the 64-bit emulator could do a 64-bit write to a 32-bit struct field. It happened to be harmless on Intel/AMD processors. Corrected. (Thanks to Mikael Pettersson.)
Own Id: OTP-8877
A bug in
Own Id: OTP-8889
Calling
Own Id: OTP-8914
The ERTS internal rwlock implementation could get into an inconsistent state. This bug was very seldom triggered, but could be during heavy contention. The bug was introduced in R14B (erts-5.8.1).
The bug was most likely to be triggered when using the
Own Id: OTP-8925 Aux Id: OTP-8544
Tracing to port could cause an emulator crash when unloading the trace driver.
Own Id: OTP-8932
Removed use of CancelIoEx on Windows that had been shown to cause problems with some drivers.
Own Id: OTP-8937
The fallback implementation used when no native atomic implementation was found did not compile. (Thanks to Patrick Baggett, and Tuncer Ayaz)
Own Id: OTP-8944
Some integer values used during load balancing could under rare circumstances wrap causing a load unbalance between schedulers.
Own Id: OTP-8950
The windows VM now correctly handles appending to large files (> 4GB).
Own Id: OTP-8958
Name resolving of IPv6 addresses has been implemented for Windows versions that support it. The use of ancient resolver flags (AI_V4MAPPED | AI_ADDRCONFIG) to the getaddrinfo() function has been removed since e.g FreeBSD regard mapped IPv4 addresses to be a security problem and the semantics of the address configured flag is uncertain.
Own Id: OTP-8969
The help texts produced by the
Own Id: OTP-8859
When the runtime system had fewer schedulers than logical processors, the system could get an unnecessarily large amount reader groups.
Own Id: OTP-8861
Own Id: OTP-8878
The Erlang VM now supports Unicode filenames. The feature is turned on by default on systems where Unicode filenames are mandatory (Windows and MacOSX), but can be enabled on other systems with the '+fnu' emulator option. Enabling the Unicode filename feature on systems where it is not default is however considered experimental and not to be used for production. Together with the Unicode file name support, the concept of "raw filenames" is introduced, which means filenames provided without implicit unicode encoding translation. Raw filenames are provided as binaries, not lists. For further information, see stdlib users guide and the chapter about using Unicode in Erlang. Also see the file module manual page.
*** POTENTIAL INCOMPATIBILITY ***
Own Id: OTP-8887
Buffer overflows have been prevented in
Own Id: OTP-8892
The runtime system is now less eager to suspend processes sending messages over the distribution. The default value of the distribution buffer busy limit has also been increased from 128 KB to 1 MB. This in order to improve throughput.
Own Id: OTP-8901
The distribution buffer busy limit can now be configured
at system startup. For more information see the
documentation of the
Own Id: OTP-8912
The inet driver internal buffer stack implementation has been rewritten in order to reduce lock contention.
Own Id: OTP-8916
New ETS option
Own Id: OTP-8922 Aux Id: seq11658
There is now a new function inet:getifaddrs/0 modeled after C library function getifaddrs() on BSD and LInux that reports existing interfaces and their addresses on the host. This replaces the undocumented and unsupported inet:getiflist/0 and inet:ifget/2.
Own Id: OTP-8926
Support for detection of CPU topology and binding of schedulers on FreeBSD 8 have been added. (Thanks to Paul Guyot)
Own Id: OTP-8939
Several bugs related to hibernate/3 and HiPE have been corrected. (Thanks to Paul Guyot.)
Own Id: OTP-8952
Support for soft and hard links on Windows versions and filesystems that support them is added.
Own Id: OTP-8955
The win32 virtual machine is now linked large address aware. his allows the Erlang VM to use up to 3 gigs of address space on Windows instead of the default of 2 gigs.
Own Id: OTP-8956
Fix that the documentation top index generator can handle an Ericsson internal application group.
Own Id: OTP-8875
In embedded mode, on_load handlers that called
Also extended the
Own Id: OTP-8902 Aux Id: seq11703
Windows 2003 and Windows XP pre SP3 would sometimes not start the Erlang R14B VM at all due to a bug in the cpu topology detection. The bug affects Windows only, no other platform is even remotely affected. The bug is now corrected.
Own Id: OTP-8876
Very small floating point numbers generated errors when converting from list to float in some versions of the VM, this is now corrected so that i.e. list_to_float("1.0e-324"). returns 0.0 in all versions of Erlang.
Own Id: OTP-7178
Windows Vista and Windows 7 file system virtualization, which makes "old style" windows programs execute in a file system sandbox, was previously unintentionally turned on for the Erlang VM. This is now corrected so that i.e. writes to C:\Program Files\. without administrator privileges will fail.
Own Id: OTP-7405
Fix faulty 64-bit integer term output from drivers. Large 64-bits integers did not generate correct bignums and could even cause emulator crash. Only affects drivers using ERL_DRV_INT64 or ERL_DRV_UINT64, introduced in R13B03.
Own Id: OTP-8716
Fixed: inet:setopts(S, [{linger,{true,2}}]) returned {error,einval} for SCTP sockets. The inet_drv had a bug when checking the option size.
Own Id: OTP-8726 Aux Id: seq11617
Fix libm linking with --as-needed flag
When building with "--as-needed" linker flags on Linux the build will fail. This has now been fixed.
(Thanks to Christian Faulhammer)
Own Id: OTP-8728
gen_udp:connect/3 was broken for SCTP enabled builds. It did not detect remote end errors as it should.
Own Id: OTP-8729
Reduce the risk of integer wrapping in bin vheap size counting.
The vheap size series will now use the golden ratio instead of doubling and fibonacci sequences.
Own Id: OTP-8730
ETS ordered_set containing
Own Id: OTP-8732
reference() has been substituted for ref() in the documentation.
Own Id: OTP-8733
When a native compiled module called a not loaded non-native compiled module that had an on_load function, the export entries were trashed after code loading so on the next call from the native compiled module to the non-native compiled the emulator crashed. This bug has now been fixed.
Own Id: OTP-8736
HiPE-enabled Erlang VMs running on BSD systems sometimes generated messages like "Yikes! erts_alloc() returned misaligned address 0x8016a512c". Fixed. (Thanks to Mikael Pettersson.)
Own Id: OTP-8769
A race condition in
Own Id: OTP-8773
Removed some potential vulnerabilities from the Erlang Port Mapper Daemon (epmd) and straightened up access control. Also removed hazardous interfaces allowing anyone on a machine to forcefully unregister other nodes. This means that the ei_unregister/erl_unregister interfaces in erl_interface is rendered not only error prone and mystifying as before, but totally ineffective. The old behaviour of unchecked node unregistering can be restored if needed, see epmd documentation for details.
*** POTENTIAL INCOMPATIBILITY ***
Own Id: OTP-8780
Building in a source tree without prebuilt platform independent build results failed on the SSL examples when:
Own Id: OTP-8791
inet:getsockopt for SCTP sctp_default_send_param had a bug to not initialize required feilds causing random answers. It is now corrected.
Own Id: OTP-8795 Aux Id: seq11655
The hipe_bifs:get_hrvtime/0 BIF now always returns a real value even if the "perfctr" Linux kernel extension is not available. It used to return a dummy value. (Thanks to Mikael Pettersson.)
Own Id: OTP-8798
Calling a native-code compiled module with an
Own Id: OTP-8799
The emulator could crash while writing a crash dump if native-compiled modules had been loaded. (Thanks to Paul Guyot.)
Own Id: OTP-8801
The garbage collector could crash if invoked from native-compiled code after a call to a BIF. (Thanks to Paul Guyot.)
Own Id: OTP-8821
A rare memory leak in binary:matches is removed
Own Id: OTP-8823
For a socket in the HTTP packet mode, the return value
from
*** POTENTIAL INCOMPATIBILITY ***
Own Id: OTP-8831
ets:select_reverse/{1,2,3} are now documented.
Own Id: OTP-7863
External format of integers changed to make full use of all 32 bits of INTEGER_EXT. This is a compatible change as old code can read full 32-bit integers but only produce 28-bit integers as INTEGER_EXT.
Own Id: OTP-8540 Aux Id: seq11534
Large parts of the
Most notable improvement is a reader optimized rwlock
implementation which dramatically improve the performance
of read-lock/read-unlock operations on multi processor
systems by avoiding ping-ponging of the rwlock cache
lines. The reader optimized rwlock implementation is used
by miscellaneous rwlocks in the runtime system that are
known to be read-locked frequently, and can be enabled on
ETS tables by passing the
There is also a new implementation of rwlocks that is not optimized for readers. Both implementations interleaves readers and writers during contention as opposed to, e.g., the NPTL (Linux) pthread rwlock implementation which use either a reader or writer preferred strategy. The reader/writer preferred strategy is problematic since it starves threads doing the non-preferred operation.
The new rwlock implementations in general performs better in ERTS than common pthread implementations. However, in some extremely heavily contended cases this is not the case. Such heavy contention can more or less only appear on ETS tables. This when multiple processes do very large amounts of write locked operations simultaneously on the same table. Such use of ETS is bad regardless of rwlock implementation, will never scale, and is something we strongly advise against.
The new rwlock implementations depend on atomic operations. If no native atomic implementation is found, a fallback solution will be used. Using the fallback implies a performance degradation. That is, it is more important now than before to build OTP with a native atomic implementation.
The
The
The changed API of the
Note: When building for x86, the
Own Id: OTP-8544
erlang:localtime_to_universaltime({{2008, 8, 1}, {0, 0, 0}},true) when TZ=UTC now behaves consistently on all Unix platforms.
The problem fixed was originally reported by Paul Guyot on erlang-bugs mailing list:
http://www.erlang.org/pipermail/erlang-bugs/2008-November/001077.html
Own Id: OTP-8580
Optimization reducing memory consumption by two words per ETS object.
Own Id: OTP-8737
Fixes for unsupported halfword-emulator
Own Id: OTP-8745
NIF 64-bit integer support;
Own Id: OTP-8746
Alignment of trailing data in messages has been adjusted. This in order to be able to pass data of any type as trailing data in the future.
Own Id: OTP-8754
The obsolete/driver.h header file has been removed. It has been obsolete and deprecated since R8B. Drivers that still include obsolete/driver.h must be updated to include erl_driver.h.
*** POTENTIAL INCOMPATIBILITY ***
Own Id: OTP-8758
Added erlang:system_info(build_type) which makes it easier to chose drivers, NIF libraries, etc based on build type of the runtime system.
The NIF library for crypto can now be built for valgrind and/or debug as separate NIF libraries that will be automatically loaded if the runtime system has been built with a matching build type.
Own Id: OTP-8760
Further lessened the memory requirements of ETS objects.
Own Id: OTP-8762
The broken elib_malloc alternate memory allocator has
been removed.
Own Id: OTP-8764
Calling
The CPU topology is now automatically detected on Windows
systems with less than 33 logical processors. The runtime
system will now, also on Windows, by default bind
schedulers to logical processors using the
Own Id: OTP-8765
The SMP ERTS internal child waiter thread used on Linux system with NPTL was unintentionally disabled during cross compilation rewrites (OTP-8323 in R13B03). It has now been re-enabled. Enabling it again gives a slight performance improvement.
Own Id: OTP-8774
Own Id: OTP-8775
The scheduler wakeup threshold is now possible to adjust
at system boot. For more information see the
Own Id: OTP-8811
The undocumented function inet:ifget/2 has been improved to return interface hardware address (MAC) on platforms supporting getaddrinfo() (such as BSD unixes). Note it still does not work on all platforms for example not Windows nor Solaris, so the function is still undocumented.
Buffer overflow and field init bugs for inet:ifget/2 and inet:getservbyname/2 has also been fixed.
Thanks to Michael Santos.
Own Id: OTP-8816
Optimizations for MIPS when using gcc atomics. (Thanks to Steve Vinoski)
Own Id: OTP-8834
Lock optimization in timer functionality.
Own Id: OTP-8835
Fix epmd and build environment to build on VxWorks
Own Id: OTP-8838
Driver threads, such as async threads, using
Own Id: OTP-8475
The use of
The
The
The
(Thanks to Steve Vinoski for reporting these issues)
Own Id: OTP-8484
A call to the BIF
Own Id: OTP-8487
The runtime system crashed if fewer logical processors
were found than reported by
Own Id: OTP-8549
Fix memory management bug causing crash of non-SMP emulator with async threads enabled. The bug did first appear in R13B03.
Own Id: OTP-8591 Aux Id: seq11554
Port locks could be prematurely destroyed.
Own Id: OTP-8612
The
Own Id: OTP-8618
When kernel poll has been enabled, a livelock could in rare circumstances occur. Problem reported by Chetan Ahuja, fix by Mikael Pettersson.
Own Id: OTP-8632
Windows: Closing port of program that stalled without reading all data could deadlock scheduler thread.
Own Id: OTP-8641
On some combination of Montavista Linux on Cavium Octeon processors, some socket-related system calls returned other numbers than -1 for errors. This caused a core dump in inet_drv.c. Now the code works around this problem.
Own Id: OTP-8654
Missing memory barriers in
Own Id: OTP-8658
Own Id: OTP-8662
Extreme combinations of register/unregister in a highly parallell SMP application could crash the VM. The error is corrected.
Own Id: OTP-8663
On Windows, files are now opened with FILE_SHARE_DELETE to get closer to Unix semantics.
Own Id: OTP-8667
Own Id: OTP-8675
Fix bug causing
Own Id: OTP-8685
Own Id: OTP-8701
A user defined CPU topology set via a call to
Own Id: OTP-8710
The grammar for match specifications in ERTS users guide only described the tracing dialect of match specifications. An informal grammar for the ETS dialect is added.
Own Id: OTP-8086 Aux Id: seq11333
The module binary from EEP31 (and EEP9) is implemented.
Own Id: OTP-8217
New NIF API function
Own Id: OTP-8474
The guard BIF
Own Id: OTP-8477
Added function
Added functions to create and extract escripts. See
The undocumented function
Record fields has been annotated with type info. Source files as been adapted to fit within 80 chars and trailing whitespace has been removed.
Own Id: OTP-8521
A regular expression with many levels of parenthesis could cause a buffer overflow. That has been corrected. (Thanks to Michael Santos.)
Own Id: OTP-8539
Own Id: OTP-8548
New NIF features:
And
some incompatible changes made to the API. For more
information see the warning text in
*** POTENTIAL INCOMPATIBILITY ***
Own Id: OTP-8555
If the '
Own Id: OTP-8559
When defining macros the closing right parenthesis before the dot is now mandatory.
*** POTENTIAL INCOMPATIBILITY ***
Own Id: OTP-8562
Local and imported functions now override the auto-imported BIFs when the names clash. The pre R14 behaviour was that auto-imported BIFs would override local functions. To avoid that old programs change behaviour, the following will generate an error:
Doing a call without explicit module name to a local function having a name clashing with the name of an auto-imported BIF that was present (and auto-imported) before OTP R14A
Explicitly importing a function having a name clashing with the name of an autoimported BIF that was present (and autoimported) before OTP R14A
Using any form of the old compiler directive
If the BIF was added or auto-imported in OTP R14A or later, overriding it with an import or a local function will only result in a warning,
To resolve clashes, you
can either use the explicit module name
The
change makes it possible to add auto-imported BIFs
without breaking or silently changing old code in the
future. However some current code ingeniously utilizing
the old behaviour or the
*** POTENTIAL INCOMPATIBILITY ***
Own Id: OTP-8579
A bug in re that could cause certain regular expression matches never to terminate is corrected. (Thanks to Michael Santos and Gordon Guthrie.)
Own Id: OTP-8589
The erlang:open_port spawn and spawn_executable
directives can include an
Own Id: OTP-8614
Own Id: OTP-8623
The functions file:advise/4 and file:datasync/1 have been added. (Thanks to Filipe David Manana.)
Own Id: OTP-8637
New NIF API functions:
Own Id: OTP-8640
Support for using gcc's built-in functions for atomic memory access has been added. This functionallity will be used if available and no other native atomic implementation in ERTS is available.
Own Id: OTP-8659
The number of spinlocks used when implementing atomic fall-backs when no native atomic implementation is available has been increased from 16 to 1024.
Own Id: OTP-8660
Writer preferred pthread read/write locks has been enabled on Linux.
Own Id: OTP-8661
The runtime system will by default bind schedulers to
logical processors using the
NOTE: If the Erlang runtime system is the only
operating system process that binds threads to logical
processors, this improves the performance of the runtime
system. However, if other operating system processes (as
for example another Erlang runtime system) also bind
threads to logical processors, there might be a
performance penalty instead. If this is the case you, are
are advised to unbind the schedulers using the
Own Id: OTP-8666
The recently added BIFs erlang:min/2, erlang:max/2 and erlang:port_command/3 are now auto-imported (as they were originally intended to be). Due to the recent compiler change (OTP-8579), the only impact on old code defining it's own min/2, max/2 or port_command/3 functions will be a warning, the local functions will still be used. The warning can be removed by using -compile({no_auto_import,[min/2,max/2,port_command/3]}). in the source file.
*** POTENTIAL INCOMPATIBILITY ***
Own Id: OTP-8669 Aux Id: OTP-8579
There is a new option 'exclusive' to file:open/2 that uses the OS O_EXCL flag where supported to open the file in exclusive mode.
Own Id: OTP-8670
Now, binary_to_term/2 is auto-imported. This will cause a compile warning if and only if a module has got a local function with that name.
*** POTENTIAL INCOMPATIBILITY ***
Own Id: OTP-8671
Alignment of scheduler data and run queues were adjusted.
Own Id: OTP-8673
Call time breakpoint tracing
Teach call count tracing to use atomics
Own Id: OTP-8677
Note: The API for the
*** POTENTIAL INCOMPATIBILITY ***
Own Id: OTP-8706
Two bugs in gen_sctp has been corrected: getopts/setopts hence also send could only be called from socket owner, and options 'linger', 'rcvbuf' and 'sndbuf' was read from wrong protocol layer hence read wrong values by getopts.
Own Id: OTP-9544
Driver threads, such as async threads, using
Own Id: OTP-8475
A call to the BIF
Own Id: OTP-8487
Fix memory management bug causing crash of non-SMP emulator with async threads enabled. The bug did first appear in R13B03.
Own Id: OTP-8591 Aux Id: seq11554
Fix
Own Id: OTP-8336
Processes and/or ports could get stuck on a blocked
scheduler when
Processes and/or ports could get stuck on an offline
scheduler when schedulers online were reduced using
Own Id: OTP-8342
Building on Windows will now work if the paths to
Own Id: OTP-8345
EPMD now correctly handles the extra data field which can be given in the ALIVE2_REQ request and retrieved in the PORT2_RESP response. (Thanks to Klas Johansson.)
Own Id: OTP-8361
The configure test for reliable floating point exceptions has been update to work on modern versions of Mac OS X. (Thanks to Trannie Carter.)
Own Id: OTP-8368
ERTS makefiles used to detect the use of a gcc C compiler by checking if CC equaled gcc. That is, the makefiles failed to detect gcc C compilers with other command line names than gcc. `configure' now substitute GCC into the makefiles. If CC is a gcc C compiler, GCC will have the value yes. (Thanks to Jean-Sébastien Pédron)
Own Id: OTP-8373
ETS bug causing the
Own Id: OTP-8377 Aux Id: seq11442
Immediately repeated multi-scheduling block/unblock
cycles using
Own Id: OTP-8386
A number of bugs concerning re and unicode are corrected:
re:compile no longer loses unicode option, which also fixes bug in re:split.
re:replace now handles unicode charlist replacement argument
re:replace now handles unicode RE charlist argument correctly
re:replace now handles binary unicode output correctly when nothing is replaced.
Most code, testcases and error isolation done by Rory Byrne.
Own Id: OTP-8394
The loading of native code was not properly atomic in the SMP emulator, which could cause crashes. Also a per-MFA information table for the native code has now been protected with a lock since it turns that it could be accessed concurrently in the SMP emulator. (Thanks to Mikael Pettersson.)
Own Id: OTP-8397
Fix processes in exiting status that are about to be scheduled, to not be allowed to garbage collect.
Own Id: OTP-8420
Removed bogus "\011" character sequence in documentation.
Own Id: OTP-8422
The resolver routines failed to look up the own node name as hostname, if the OS native resolver was erroneously configured, bug reported by Yogish Baliga, now fixed.
The resolver routines now tries to parse the hostname as an IP string as most OS resolvers do, unless the native resolver is used.
The DNS resolver inet_res and file resolver inet_hosts now do not read OS configuration files until they are needed. Since the native resolver is default, in most cases they are never needed.
The DNS resolver's automatic updating of OS configuration file data (/etc/resolv.conf) now uses the 'domain' keyword as default search domain if there is no 'search' keyword.
Own Id: OTP-8426 Aux Id: OTP-8381
The re module: A regular expression with an option change at the start of a pattern that had top-level alternatives could cause overwriting and/or a crash. (Thanks to Michael Santos.)
Own Id: OTP-8438
Harmless buffer overflow by one byte in asn1 and ram_file_drv.
Own Id: OTP-8451
Improved GC performance after BIF/NIF call when a lot of heap fragments was created. This will mainly benefit NIFs that return large compound terms.
Own Id: OTP-8240
Incompatible changes in the experimental NIF feature.
Read more in the documentation of
*** POTENTIAL INCOMPATIBILITY ***
Own Id: OTP-8304
Cross compilation improvements and other build system improvements.
Most notable:
(Thanks to Henrik Riomar for suggestions and testing)
(Thanks to Winston Smith for the AVR32-Linux cross configuration and testing)
*** POTENTIAL INCOMPATIBILITY ***
Own Id: OTP-8323
NIF improvements:
Own Id: OTP-8335
Minor alignment adjustments of scheduler specific data.
Own Id: OTP-8341
The documentation is now possible to build in an open source environment after a number of bugs are fixed and some features are added in the documentation build process.
- The arity calculation is updated.
- The module prefix used in the function names for bif's are removed in the generated links so the links will look like "http://www.erlang.org/doc/man/erlang.html#append_element-2" instead of "http://www.erlang.org/doc/man/erlang.html#erlang:append_element-2".
- Enhanced the menu positioning in the html documentation when a new page is loaded.
- A number of corrections in the generation of man pages (thanks to Sergei Golovan)
- The legal notice is taken from the xml book file so OTP's build process can be used for non OTP applications.
Own Id: OTP-8343
There is new
Own Id: OTP-8367
The default settings for garbage collection of binaries
has been adjusted to be less aggressive than in R13B03.
It is now also possible configure the settings for binary
GC. See the documentation for
Own Id: OTP-8370
A bug causing memory corruption in re:run() has been corrected. (Thanks to Yamashina Hio.)
Own Id: OTP-8375
The
Own Id: OTP-8382
Explicit top directories in archive files are now optional.
For example, if an archive (app-vsn.ez) just contains an app-vsn/ebin/mod.beam file, the file info for the app-vsn and app-vsn/ebin directories are faked using the file info from the archive file as origin. The virtual direcories can also be listed. For short, the top directories are virtual if they does not exist.
Own Id: OTP-8387
An unnecessary lock operation in os:timestamp/0 has been eliminated, making it slightly more efficient. (Thanks to Jonas Falkevik and Tuncer Ayaz.)
Own Id: OTP-8390
There is a new
Own Id: OTP-8405
Fixed numerous compiler warnings generated by gcc 4.4.1 and tile-cc 2.0.1.78377 when compiling the runtime system.
Own Id: OTP-8412
Own Id: OTP-8415
HiPE now works in the 64-bit emulator on Mac OS X. (Thanks to Geoff Cant.)
Own Id: OTP-8416
Improved handling of symbolic links to escripts
Own Id: OTP-8417
Add lock profiling tool.
The Lock profiling tool, lcnt, can make use of the internal lock statistics when the runtime system is built with this feature enabled.
This provides a mechanism to examine potential lock bottlenecks within the runtime itself.
- Add erts_debug:lock_counters({copy_save, bool()}). This option enables or disables statistics saving for destroyed processes and ets-tables. Enabling this might consume a lot of memory.
- Add id-numbering for lock classes which is otherwise undefined.
Own Id: OTP-8424
Removed spurious options to the emulator from escript.
Own Id: OTP-8427
Minor documentation fixes. Mainly anchor adjustments.
Own Id: OTP-8457
An insufficient stack allocation was made when reading CPU information on BSD operating systems. (Thanks Michael Turner and Akira Kitada)
Own Id: OTP-8207
A bug when supplying an argument without a dash directly after the program name when starting erlang could prevent distribution to start. This is now corrected.
Own Id: OTP-8209
A ticker process could potentially be blocked indefinitely trying to send a tick to a node not responding. If this happened, the connection would not be brought down as it should.
Own Id: OTP-8218
Using certain firewalls (i.e. MS IAS Client and certain versions of COMODO) could expose an undocumented behaviour in the Win32 socket interface causing the name resolution calls to hang infinitely. This is now worked around by adding possibilities for port programs under Windows to use overlapped I/O on their standard input/output file handles.
Own Id: OTP-8230
Fixed bug on ETS tables with
Own Id: OTP-8242
The
The following BIFs behaviors can be modeled as if an
asynchronous
When
Own Id: OTP-8245
Errors in the
Own Id: OTP-8257
Low watermark socket option modified high watermark instead of low watermark in the inet_driver. (Thanks to Feng Yu and Tuncer Ayaz)
Own Id: OTP-8279
A race condition could cause the runtime system with SMP support to end up in a completely unresponsive state.
Own Id: OTP-8297
The use of
Own Id: OTP-8193
The documentation is now built with open source tools (xsltproc and fop) that exists on most platforms. One visible change is that the frames are removed.
Own Id: OTP-8201
A new garbage collecting strategy for binaries which is more aggressive than the previous implementation. Binaries now has a virtual binary heap tied to each process. When binaries are created or received to a process it will check if the heap limit has been reached and if a reclaim should be done. This imitates the behavior of ordinary Erlang terms. The virtual heaps are grown and shrunk like ordinary heaps. This will lessen the memory footprint of binaries in a system.
Own Id: OTP-8202
The
For more information see the
Own Id: OTP-8205
[escript] The restriction that the first line in escripts
must begin with
[escript] Some command line options to the escript executable has now been documented. For example you can run an escript in the debugger by just adding a command line option.
[escript] The documentation of the escript header syntax
has been clarified. For example the header is optional.
This means that it is possible to directly "execute"
Own Id: OTP-8215
The instruction for building OTP on Windows was outdated and incomplete, the document is updated.
Also the otp_build script required windows drives to show up in Cygwin using the /cygdrive prefix. That requirement is now removed.
Own Id: OTP-8219
A module can have native implemented functions (NIFs)
that are dynamically loaded by calling
Own Id: OTP-8220
The
Own Id: OTP-8221
The
Own Id: OTP-8225
'
Own Id: OTP-8236
On Windows, open_port({spawn,Command},Opts) could not run executables with spaces in the path or filename, regardless of quoting efforts. While open_port({spawn_executable,Exec},Opts) can run any executable, it was still impossible to use 'spawn' to do the same thing. This is now corrected.
Own Id: OTP-8055
The scheduler bind type
The new scheduler bind type
Own Id: OTP-8063
Automatically detected CPU topology on Linux system could
erroneously contain logical processors with
Own Id: OTP-8064
When the minimal term [] (end of list) was sent as the complete message to a process on another node, and received there, it could not be decoded. This bug is now corrected. Fortunately [] is uncommon as the complete message in real applications but it is a serious bug anyway.
Own Id: OTP-8092
A bug when the floating point exception pointer was not initialized has been corrected. It manifested itself on CentOS 5.1 sometimes when a floating point value was sent to a remote node. Bug reported and patch suggested by David Reiss, confirmed by Mikael Pettersson.
Some build problems on IRIX was also corrected. Problem reported by Patrick Baggett, patch by Mikael Pettersson.
Own Id: OTP-8095
A terminating process could erroneously unregister a name for another process. This could occur under the following conditions: The name of the terminating process was unregistered and then registered for another process simultaneously as the process that first had the name was terminating.
Own Id: OTP-8099 Aux Id: seq11344
Running erlc in a very deep directory (with a path length
of more 256 or more characters) would cause the emulator
to crash in a call to
Own Id: OTP-8124
A deadlock of the runtime system could occur when unregistering the name of a port.
Own Id: OTP-8145
Own Id: OTP-8157
The pthread rwlock implemention on Linux could cause starvation of writers. We, therefore, now use our own rwlock implementation on Linux.
Own Id: OTP-8158
Open source Erlang builds are updated to work well on Snow Leopard (MacOS X 10.6)
Own Id: OTP-8168
A call to
Own Id: OTP-8169
An error in erlang:system_profile/2 could cause timestamped messages to arrive out of order in the SMP case. This has now been fixed.
Own Id: OTP-8171
Own Id: OTP-8192
The async thread pool in the runtime system without SMP support used a memory allocator that was not thread safe for async jobs.
Own Id: OTP-8194
Processor internal NUMA nodes are now supported in the
ERTS internal CPU topology representation. For more
information see the documentation of the
Own Id: OTP-8041
Documentation for ets improved about concurrency.
Own Id: OTP-8050
Emulator flags in an escript were earlier inherited to
emulators started from from the emulator running the
escript. For example when an escript invoked
Escript filenames may now contain dots.
Own Id: OTP-8060
Made some BIFs non-recursive (relational operators,hash and phash) to limit internal stack usage.
Own Id: OTP-8065
Fixed Windows specific bug in erl_prim_loader. Now it handles the root directory (e.g. c:/) better. This bug affected the directory listing in the debugger.
Own Id: OTP-8080
A TCP socket with option
Own Id: OTP-8102
The maximum size of the export table has been raised from 65536 to 524288 entries.
Own Id: OTP-8104 Aux Id: seq11345
The file module has now a read_line/1 function similar to the io:get_line/2, but with byte oriented semantics. The function file:read_line/1 works for raw files as well, but for good performance it is recommended to use it together with the 'read_ahead' option for raw file access.
Own Id: OTP-8108
Fixed bug causing emulator crash when reading a term in external format containing a corrupt list with a negative length.
Own Id: OTP-8117
New emulator flag
Own Id: OTP-8119
The Windows utility Erlsrv, run in interactive mode now accepts options for registering internal service name and description field of Windows registry database.
Own Id: OTP-8132
A new option
Own Id: OTP-8143
I/O tasks could unnecessarily be rescheduled. This was harmless, but not useful work.
Own Id: OTP-8148
Minor improvements of
Own Id: OTP-8152
New configuration option to enable use of shared zlib.
Own Id: OTP-8155
Fixed smp bug in ETS that could cause emulator crash when
table with more than 1000 objects accessed by several
processes, including calls to variants of
Own Id: OTP-8166 Aux Id: seq11392
The code path interpretation is now more relaxed. The flag -code_path_choice now defaults to relaxed instead of strict. See the documentation of code and init for more info.
Own Id: OTP-8170
Load balancing of run queues and check for I/O are triggered more often than before in situations where processes are scheduled often but are doing very little work each time they execute.
Own Id: OTP-8172
Call tracing binary comprehensions would cause an emulator crash. (Thanks to Paul Mineiro.)
Own Id: OTP-8179
Own Id: OTP-8180
Crash dumps should now cause less problems for the crashdump_viewer application. (For processes where arity was non-zero, the arguments are now longer printed - they used to be printed in a format that was not parseable.)
Own Id: OTP-7472 Aux Id: seq11019, 11292
Processes could potentially get stuck on an offline scheduler.
Own Id: OTP-7990
Own Id: OTP-7997
A process could under very rare circumstances erroneously be resumed.
Own Id: OTP-8000
Load balancing between schedulers could under rare circumstances cause an emulator crash.
Own Id: OTP-8008
Own Id: OTP-8022
Major improvements of the Erlang distribution for Erlang runtime systems with SMP support. Previously distribution port locks were heavily contended, and all encoding and decoding for a specific distribution channel had to be done in sequence. Lock contention due to the distribution is now negligible and both encoding and decoding of Erlang messages can be done in parallel.
The old atom cache protocol used by the Erlang distribution has been dropped since it effectively prevented all parallel encoding and decoding of messages passed over the same distribution channel.
A new atom cache protocol has been introduced which isolates atom cache accesses and makes parallel encoding and decoding of messages passed over the same distribution channel possible. The new atom cache protocol also use an atom cache size 8 times larger than before. The new atom cache protocol is documented in the ERTS users guide.
Erlang messages received via the distribution are now decoded by the receiving Erlang processes without holding any distribution channel specific locks. Erlang messages and signals sent over the distribution are as before encoded by the sending Erlang process, but now without holding any distribution channel specific locks during the encoding. That is, both encoding and decoding can be and are done in parallel regardless of distribution channel used.
The part that cannot be parallelized is the atom cache updates. Atom cache updates are therefore now scheduled on the distribution port. Since it is only one entity per distribution channel doing this work there is no lock contention due to the atom cache updates.
The new runtime system does not understand the old atom cache protocol. New and old runtime systems can however still communicate, but no atom cache will be used.
Own Id: OTP-7774
Fixed a bug that caused error logging from
Own Id: OTP-7898 Aux Id: seq11304
Improved SMP concurrency for ETS tables. Several mutating
operations can now be performed truly concurrent on
different records of the same table. To support this, the
table has to be created with option
Own Id: OTP-7922
erl (that is erl.exe and dyn_erl) and erlexec has been made more dynamic so no hard coded paths needs to added at installation time to erl (that is erl.ini and erl). Reltool will make use of this in a future release.
Own Id: OTP-7952
Added functionality to get higher resolution timestamp from system. The erlang:now function returns a timestamp that's not always consistent with the actual operating system time (due to resilience against large time changes in the operating system). The function os:timestamp/0 is added to get a similar timestamp as the one being returned by erlang:now, but untouched by Erlangs time correcting and smoothing algorithms. The timestamp returned by os:timestamp is always consistent with the operating systems view of time, like the calendar functions for getting wall clock time, but with higher resolution. Example of usage can be found in the os manual page.
Own Id: OTP-7971
Two new options are added to open_port - spawn_executable which runs external executables in a controlled way, and spawn_driver which only opens port to loaded Erlang drivers. See the erlang manual page for details.
Own Id: OTP-7995
New functionality in ETS to transfer the ownership of a
table. A table can either change owner be declaring an
"heir", another process that will inherit the table if
the owner terminates. A table can also change owner by
calling a new function
Own Id: OTP-8006
Updates to Tilera build environment.
Own Id: OTP-8009
A stack trace was unnecessarily saved during process termination.
Own Id: OTP-8014
User defined CPU topology and scheduler bind type can now
be set from the command line when starting an emulator.
For more information see the documentation of the
The CPU topologies returned from
Own Id: OTP-8030
Various fixes in ETS:
Own Id: OTP-8040
Fixed a bug on Windows that could make
Own Id: OTP-7816
The runtime system could under rare circumstances crash during load balancing.
Own Id: OTP-7908 Aux Id: otp-7500
Own Id: OTP-7916 Aux Id: seq11249
A message buffer memory leak in the runtime system without smp support has been fixed.
Own Id: OTP-7941
Attempting to append a binary of 16Mb or greater to
another binary using the bit syntax would cause a
Own Id: OTP-7942
The runtime system with SMP support failed to terminate
the caller of
Own Id: OTP-7946
Rudimentary support for cross compiling is added to the source release. The support is still in its infancy and has only been used to cross compile on Linux for a different cpu architecture and a different Linux version, but should be extendible to support other platforms as well. The cross configuration files with examples are placed in $ERL_TOP/xcomp/. View README.xcomp and run $ERL_TOP/otp_build -help for further information.
Own Id: OTP-7854
The escape sequence
Own Id: OTP-7891 Aux Id: OTP-7855
The
Also fixed some minor issues in
Own Id: OTP-7894
Several glitches and performance issues in the Unicode and I/O-system implementation of R13A have been corrected.
Own Id: OTP-7896 Aux Id: OTP-7648 OTP-7887
Minor documentation improvements of the
Own Id: OTP-7901 Aux Id: OTP-7777
There is a new BIF
Own Id: OTP-7913
OpenSource:
FreeBSD leap-seconds are handled according to patch submitted by OpenSource user Kenji Rikitake. No test case covers this functionality (unsupported platform).
Own Id: OTP-7609
A corrected bug in
Own Id: OTP-7665
A new driver call-back
Own Id: OTP-7670
A bug fixed for TCP sockets with option
Own Id: OTP-7682 Aux Id: OTP-7647
run_erl did in some cases fail to extract control sequences from to_erl (like: winsize=X,Y) and did instead send them to be interpreted by the erlang shell.
Own Id: OTP-7688
A bug in the installer on Windows not updating file associations properly is now corrected.
Own Id: OTP-7746
More space than necessary could be allocated in binaries when appending to a binary (also in a binary comprehension) and the data appended did not consist of wholes bytes (e.g. 13 bits).
Own Id: OTP-7747
The gen_sctp option sctp_peer_addr_params, #sctp_paddrparams{address={IP,Port} was erroneously decoded in the inet driver. This bug has now been corrected.
Own Id: OTP-7755
Outstanding async driver jobs leaked memory if the issuing port died before the async jobs completed.
Own Id: OTP-7784
A bug in the dynamic library loading affecting, among others, OpenSolaris is now corrected. (Thanks to Paul Fisher.)
Own Id: OTP-7796
run_erl compile errors fixed for FreeBSD
Own Id: OTP-7817
A bug in the inet driver for SCTP on Solaris showing for e.g gen_sctp:abort/1 and gen_sctp:eof/1 has been corrected. Patch suggestion by Simon Cornish.
Own Id: OTP-7866
The order of objects visited in select for ordered_set is now documented.
Own Id: OTP-7339
The runtime system with SMP support now uses multiple, scheduler specific run queues, instead of one globally shared run queue.
The lock protecting the shared run queue was heavily contended, and the shared run queue also caused Erlang processes to randomly migrate between schedulers with negative cache effects as a result.
With the current scheduler specific run queue solution, lock contention due to run queue protection has been reduced, and Erlang processes are only migrated when needed to balance the load between the schedulers. The reduced amount of migration also reduce lock contention on locks protecting the scheduler specific instances of the erts internal memory allocators.
The scheduler specific run queues are also a necessity for a lot of future planned NUMA (Non-Uniform Memory Access) specific optimizations.
Own Id: OTP-7500
Support for Unicode is implemented as described in EEP10. Formatting and reading of unicode data both from terminals and files is supported by the io and io_lib modules. Files can be opened in modes with automatic translation to and from different unicode formats. The module 'unicode' contains functions for conversion between external and internal unicode formats and the re module has support for unicode data. There is also language syntax for specifying string and character data beyond the ISO-latin-1 range.
The interactive shell will support input and output of unicode characters when the terminal and operating system supports it.
Please see the EEP and the io/io_lib manual pages as well as the stdlib users guide for details.
I/O-protocol incompatibilities:
The io_protocol between io_Server and client is updated to handle protocol data in unicode formats. The updated protocol is now documented. The specification resides in the stdlib users manual, which is a new part of the manual.
io module incompatibilities:
The io:put_chars, io:get_chars and io:get_line all handle and return unicode data. In the case where binaries can be provided (as to io:put_chars), they shall be encoded in UTF-8. When binaries are returned (as by io:get_line/get_chars when the io_server is set in binary mode) the returned data is also always encoded as UTF-8. The file module however still returns byte-oriented data, why file:read can be used instead of io:get_chars to read binary data in ISO-latin-1.
io_lib module incompatibilities:
io_lib:format can, given new format directives (i.e "~ts" and "~tc"), return lists containing integers larger than 255.
*** POTENTIAL INCOMPATIBILITY ***
Own Id: OTP-7648 Aux Id: OTP-7580 OTP-7514 OTP-7494 OTP-7443 OTP-7181 EEP10 EEP11
The format of the string returned by
Own Id: OTP-7649
Message passing has been further optimized for parallel execution. Serial message passing is slightly more expensive than before, but parallel send to a common receiver is much cheaper.
Own Id: OTP-7659
Lock contention on the atom table lock when decoding Erlang terms on the external format has been drastically reduced.
Own Id: OTP-7660
The undocumented, unsupported, and deprecated guard BIF
*** INCOMPATIBILITY with R12B ***
Own Id: OTP-7673
The Erlang process lock implementation has been improved by Mat Hostetter at Tilera Corporation.
Own Id: OTP-7692
A
Own Id: OTP-7725
The short-circuit operators
*** POTENTIAL INCOMPATIBILITY ***
Own Id: OTP-7748
A new BIF,
Own Id: OTP-7752
Optimization for drivers by creating small binaries direct on process heap.
Own Id: OTP-7762
There would always be a garbage collection when
evaluating
If
If
Own Id: OTP-7764
Scheduler threads can now be bound to logical processors on newer Linux and Solaris systems. More systems will be supported in the future.
In some cases performance has increased drastically when
binding schedulers. Schedulers are not bound by default,
though. This since it might cause a performance
degradation if multiple programs have bound to
processors, e.g. multiple Erlang runtime systems. For
more information see the documentation of
In order to bind scheduler threads the CPU topology need
to be known. On some newer Linux and Solaris systems the
runtime system automatically detects the CPU topology. If
the emulator isn't able to automatically detect the CPU
topology, the CPU topology can be defined. For more
information see the documentation of
Own Id: OTP-7777
The compiler will refuse to a compile file where the module name in the file differs from the output file name.
When compiling using
*** POTENTIAL INCOMPATIBILITY ***
Own Id: OTP-7793
The BIFs
Own Id: OTP-7804
The amount of schedulers online can now be changed during
operation. The amount of schedulers online defaults to
the same amount as available logical processors. For more
information see the documentation of
Own Id: OTP-7811
The deprecated functions
*** POTENTIAL INCOMPATIBILITY ***
Own Id: OTP-7812
Erts internal dynamically allocated process and port specific data for rarely used data. This is used to reduce memory usage of processes and ports that do not use specific functionality. More functionality will be moved to process and port specific data in future releases.
Own Id: OTP-7818
New packet type
Own Id: OTP-7821
The obsolete wd_keeper program for embedded Solaris systems has been removed.
Own Id: OTP-7822
Nodes belonging to different independent clusters can now co-exist on the same host with the help of a new environment variable setting ERL_EPMD_PORT.
Own Id: OTP-7826
There are new functions
Own Id: OTP-7841
The copyright notices have been updated.
Own Id: OTP-7851
Enhanced build environment for cross compilation to Tilera Tile architecture.
Support for native ethread atomics on Tilera Tile64/TilePro (Thanks to Tilera Corporation).
Own Id: OTP-7852
The escape sequences
NOTE: These new escape sequences are still considered experimental and may be changed in the R13B release.
*** POTENTIAL INCOMPATIBILITY ***
Own Id: OTP-7855
The PCRE library's exported function names are now prefixed with erts_ in the erlang emulator to avoid clashes with dynamically loaded drivers.
Own Id: OTP-7861
A runtime system with SMP support will now be built by default on most platforms if a usable posix thread library or native windows threads are found.
For more information see the top README file.
Own Id: OTP-7872
A corrected bug in
Own Id: OTP-7665
A bug fixed for TCP sockets with option
Own Id: OTP-7682 Aux Id: OTP-7647
Calling
Own Id: OTP-7731 Aux Id: seq11161
A process being garbage collected via the
Own Id: OTP-7738
A bug in inet_drv concerning gen_tcp:connect has been corrected. A connect towards a non-open port through open firewalls could sometimes erroneously be successful. Any subsequent operation would fail, though.
Own Id: OTP-6542
Floating point arithmetics in drivers could cause a runtime system crash and/or unexpected results on runtime systems with floating point exceptions enabled. Floating point exceptions are disabled unless explicitly enabled or if hipe is enabled.
Own Id: OTP-7237
A bug when many sockets got signalled simultaneously causing the emulator to panic with the message "Inconsistent, why isnt io reported?" is now corrected.
Own Id: OTP-7420
Starting erl with option "-detached" now disconnects correctly from terminal session on Unix.
Own Id: OTP-7461
Mended gdb etp-commands for ETS access.
Own Id: OTP-7538
Own Id: OTP-7543
An emulator compiled for SCTP now starts even if the dynamic libraries are not present. The SCTP driver is then of course not loaded.
Own Id: OTP-7551
To build on Mac OS X, 10.3.0 or later is now required because of fixes for two problems:
There would be a resource leak when
Signal handling in the run-time system for HiPE has
been updated to work on later versions of Mac OS X than
10.2.x. Therefore,
Thanks to Geoff Cant for the patches.
Own Id: OTP-7562
Corrected some information about the protocol between EPMD and Erlang nodes. (Thanks to Michael Regen.)
Own Id: OTP-7594
When using
Own Id: OTP-7622 Aux Id: OTP-4903, seq8379
The driver entry of a dynamically loaded driver is now copied when loaded which enables some internal optimizations. Note that drivers that modify the driver entry during execution will not work anymore. Such a miss-use of the driver interface is however not supported.
Own Id: OTP-6900
The split function is now added to the re library. Exceptions and errors from both run, replace and split are made more consistent.
Own Id: OTP-7514 Aux Id: OTP-7494
Fixed harmless compiler warnings when building the emulator and minor build changes in order to avoid unnecessary rebuilds.
Own Id: OTP-7530
There is now experimental support for loading of code
from archive files. See the documentation of
The error handling of
An
An
An
The internal module
Own Id: OTP-7548 Aux Id: otp-6622
The reallocation functionality part of the ERTS internal memory allocators, now consider current block in combination with surrounding free blocks as an alternative location for a reallocation.
Own Id: OTP-7555
There could remain false references from a process to a module that has been called earlier, so that the process would be killed if the module was reloaded. (Thanks to Richard Carlsson.)
Also, the fix for this bug also made it possible to
make stack backtraces (as returned from
Own Id: OTP-7559
Improved locking in IO-handling for better smp performance.
Own Id: OTP-7560
Improved BIF rescheduling functionality.
Own Id: OTP-7587
Loading a module compiled with Erlang/OTP R9C and calling
Own Id: OTP-7590
A process calling one of the following BIFs could under
very rare conditions deadlock in the runtime system with
SMP support:
Own Id: OTP-7582
A couple of statistics variables were not managed in a thread safe manner in the runtime system with SMP support.
Own Id: OTP-7583
An extremely rare race condition when terminating a process could potentially cause a runtime system crash.
Own Id: OTP-7584
Under certain conditions and when using run_erl/to_erl, the terminal Erlang driver (ttsl_drv) could crash the emulator by doing a division by zero due to incorrect handling of terminals reporting a zero width. For terminals reporting zero width, the driver now fallbacks to a default width of 80 and a default height of 24 (vt100), as a fallback behaviour. This fixes the crashes and also makes output on "dumb" terminals much more readable.
Own Id: OTP-7592 Aux Id: seq11073
A new
Own Id: OTP-7540
The new option
Own Id: OTP-7578 Aux Id: seq11052
Double backslashes in format string passed to the erts internal printf implementation produced erroneous results. No such format strings were passed to the erts internal printf implementation, i.e., the bug was therefore completely harmless. (Thanks to Perry Smith.)
Own Id: OTP-7408
Large files are now handled on Windows, where the filesystem supports it.
Own Id: OTP-7410
Bug fixed for
Own Id: OTP-7458
The trace option
Own Id: OTP-7484
Using 16#ffffFFFF as a timeout value in receive...after would often cause a timeout almost at once due to an 32-bit integer overflow. (Thanks to Serge Aleynikov and Matthias Lang.)
Own Id: OTP-7493
For the process that an escript runs in, the
*** POTENTIAL INCOMPATIBILITY ***
Own Id: OTP-7517
A bug in the
Own Id: OTP-7526
Performance for ETS intensive applications should now
be better in the SMP emulator. Also, ETS table
identifiers (as returned by
NOTE: Table identifiers can now be negative integers. Programs that (incorrectly) assume that table identifiers can only be positive integers might stop to work. (The type of a table identifier is intentionally not documented, and may change in a future release.)
Own Id: OTP-7348
New BIF
*** POTENTIAL INCOMPATIBILITY ***
Own Id: OTP-7404
The source code for the documentation for some applications (erts, kernel, stdlib, and several others) are now included in the source tar ball. There is currently no Makefile support for building HTML files from the source (such support will be included in a future release).
Own Id: OTP-7406
A lot of frequently accessed memory counters (erts
internal) have been removed. This since they hurt
performance on the runtime system with SMP support. As a
result
*** POTENTIAL INCOMPATIBILITY ***
Own Id: OTP-7468
Pre-allocators used for, for example, timers, and messages have been rewritten to be scheduler specific. That is, different schedulers will now allocate from different pools which reduces lock contention.
Own Id: OTP-7470
On Mac OS X, file:sync/1 now guarantees that all filesystem buffers are written to the disk by using the fcntl() with F_FULLFSYNC option. Previously, file:sync/1 called fsync(), which only guaranteed that the data had been transferred to the disk drive. (Thanks to Jan Lehnardt.)
Own Id: OTP-7471
Termination of a process that takes a long time can now be preempted, i.e., the terminating process will be rescheduled for later continuation of termination so that other processes can execute. Termination of a process that owns many and/or large ets tables typically takes a long time.
Own Id: OTP-7477
A new trace option
The
Own Id: OTP-7481
The re module is extended with repetitive matches (global option) and replacement function.
Own Id: OTP-7494 Aux Id: OTP-7181
In the section about binary construction, the reference manual now mentions what happens when an integer value does not fit into an integer segment of size N (namely, that the N least significant bits will be put into into the binary and that the most significant bits will be silently discarded). (Thanks to Edwin Fine.)
Own Id: OTP-7506
Setting the
Own Id: OTP-7520
Floating point arithmetics in drivers can cause a runtime system crash and/or unexpected results on runtime systems with floating point exceptions enabled. Floating point exceptions are disabled unless explicitly enabled or if hipe is enabled.
Own Id: OTP-7237
Binary construction with an integer field of size 0 at the end of the constructed binary (and the size given in a variable), would cause a write of one byte outside the memory reserved for the binary, which in turn could cause an emulator crash.
Own Id: OTP-7422
A race condition in the dynamic driver implementation could cause an emulator crash. (Thanks to Paul Fisher)
Own Id: OTP-7464
Calls to
Own Id: OTP-7474
The
Own Id: OTP-7475
Operations that needed to block other threads in the
runtime system with SMP support unnecessarily waited for
async threads to block. Most important the
Own Id: OTP-7480
Calls to
Own Id: OTP-7415
Doing local call trace on bit syntax matching code that has been optimized with delayed sub-binary creation could crash the emulator.
Own Id: OTP-7399 Aux Id: seq10978
Only one to_erl process at a time is allowed to connect to the same run_erl pipe. Prevents buggy behaviour when IO from several to_erl's get interleaved.
Own Id: OTP-5107
IPv6 name resolving has now been fixed to use getaddrinfo() patch (thoroughly reworked) courtesy of Love Hörnquist-Åstrand submitted by Fredrik Thulin. It also can use gethostname2() patch (also reworked) courtesy of Mikael Magnusson for debian submitted by Sergei Golovan.
Own Id: OTP-5382
Improved error handling in run_erl
Own Id: OTP-7252
A permanent fix for the deadlock issue temporarily fixed by OTP-7260.
Own Id: OTP-7267 Aux Id: OTP-7260
./configure has been improved to find 64-bit OpenSSL libraries.
Own Id: OTP-7270
A terminating process could under very rare circumstances trigger a bug which could crash the runtime system with SMP support.
Own Id: OTP-7272
SCTP_ADDR_CONFIRMED events are now handled by gen_sctp.
Own Id: OTP-7276
binary_to_term/1 would crash the emulator if the binary data contained an external fun with non-atom module and/or function. Corrected to generate a badarg exception.
Own Id: OTP-7281
On Mac OS 10.5 (Leopard), sending to socket which the other end closes could cause the emulator to consume 100% CPU time. (Thanks to Matthias Radestock.)
Own Id: OTP-7289
The vanilla driver used on Windows could crash the
emulator and sometimes produced corrupt files. The
vanilla driver is the driver that is used when one only
pass a filename as first argument to
Own Id: OTP-7301
Faulty matching in binaries larger than 512Mb on 64bit machines fixed.(On 32bit, the size limit for binaries is still 512Mb). Thanks to Edwin Fine and Per Gustafsson for finding fault and fix.
Own Id: OTP-7309
crypto:start() on Windows caused emulator to hang on error popup window if openssl DLL was not found. Windows error popups now suppressed.
Own Id: OTP-7325
Configuration option
Own Id: OTP-7338
to_erl reports its terminal window size to run_erl in order to get output formatted accordingly
Own Id: OTP-7342
On Solaris, the
Own Id: OTP-7343 Aux Id: seq10949
A race condition in the runtime system with SMP support causing an erroneous removal of a newly created ets table has been fixed.
The race occurred when a process removed a table during
termination simultaneously as another process removed the
same table via
Own Id: OTP-7349
Own Id: OTP-7359
If the total number of allowed atoms is exceeded, there will now be a controlled termination of the emulator with a crash dump file. The emulator used to simply crash. (Thanks Howard Yeh and Thomas Lindgren.)
Own Id: OTP-7372
The break handler in werl on Windows could cause the emulator to hang or crash, that is now corrected.
Own Id: OTP-7394 Aux Id: seq10969
The configure script now tests for an serious optimization bug in gcc-4.3.0. If the bug is present, the configure script will abort (if this happens, the only way to build Erlang/OTP is to change to another version of gcc). (Thanks to Mikael Pettersson.)
Own Id: OTP-7397
On Unix, the emulator now notices when the width of the terminal has changed. (Thanks to Matthew Dempsky and Patrick Mahoney.)
Own Id: OTP-7290
There is a new function
Own Id: OTP-7308
process_info(Pid, garbage_collection) now returns more information
Own Id: OTP-7311
The
Own Id: OTP-7358
Floating point arithmetics in drivers can cause a runtime system crash on runtime systems with floating point exceptions enabled. Floating point exceptions are disabled unless explicitly enabled or if hipe is enabled.
Own Id: OTP-7237
The maximum length of an atom of 255 characters is now
strictly enforced.
Own Id: OTP-7147
A bug in "bignum handling" on some 64bit architectures could cause rem and div operations on large numbers to hang indefinitely. Rem operations involving the smallest negative number representable in 28 bits or 60 bits could also cause access violation and emulator crash. Both errors are corrected.
Own Id: OTP-7177
When doing the initial garbage collection after waking a hibernated process, a fullsweep garbage collection was unnecessarily triggered.
Own Id: OTP-7212
The beta testing module
Try it, give comments and send in bug reports!
Own Id: OTP-7225
Invalid arguments to
Own Id: OTP-7226
The runtime system with SMP support could under rare circumstances deadlock when a distribution channel was taken down while multiple simultaneous operations were performed on it.
Own Id: OTP-7260
More checksum/hash algorithms from the zlib library are now available as built in functions (like md5 hashes has been for a long time).
Own Id: OTP-7128
Minor improvements in the garbage collector.
Own Id: OTP-7139 Aux Id: OTP-7132
The switch "-detached" to the windows werl program now can create an erlang virtual machine without any main window and without a temporary console showing.
Own Id: OTP-7142
The scale factor returned by
Own Id: OTP-7175
A new BIF ets:update_element/3. To update individual elements within an ets-tuple, without having to read, update and write back the entire tuple.
Own Id: OTP-7200
A process executing the
The documentation of the
Own Id: OTP-7213
Not enough parameters were passed when sending an error report in erl_check_io.c (Thanks to Matthew Dempsky).
Own Id: OTP-7176
In rare circumstances, complex binary matching code could cause the emulator to crash or not match when it should. (Thanks to Rory Byrne.)
Own Id: OTP-7198
The
Own Id: OTP-7167
The finishing reallocation of the heap block when hibernating a process is now always moving the heap block since it drastically reduces memory fragmentation when hibernating large amounts of processes.
Own Id: OTP-7187
The SMP emulator on sparc64 erroneously used the sparc32 atomic and the sparc32 spinlock implementations which caused it to crash.
Own Id: OTP-7006
Call tracing the new guard BIFs
Own Id: OTP-7008
configuring --enable-darwin-universal or --enable-darwin-64bit on MacOSX could result in a non optimized emulator. Top level configure script now corrected.
Own Id: OTP-7014
configuring --with-gd did not produce correct include flags for percept.
Own Id: OTP-7015
Environment variables weren't handled in thread safe manner in the runtime system with SMP support on Windows.
Own Id: OTP-7035
HIPE: Corrected the choice of interface to the send/3 and setnode/3 BIFs for native-compiled code. Using the incorrect interface could, in unusual circumstances, lead to random runtime errors.
Own Id: OTP-7067
Garbage collections could become extremely slow when there were many keys in the process dictionary. (Thanks to Fredrik Svahn.)
Own Id: OTP-7068
The duplicate documentation directory in the windows installation is removed.
Own Id: OTP-7070
Documentation bugfixes and clarifications.
(Thanks to Joern (opendev@gmail.com), Matthias Lang, and Richard Carlsson.)Own Id: OTP-7079
The runtime system with SMP support not using the native atomic integer implementation part of OTP could deadlock when run on a system with more than one logical processor. That is, only the runtime system with SMP support on other hardware platforms than x86, x86_64, sparc32, and powerpc32 were effected by this bug.
Own Id: OTP-7080
The break handling code (run when Ctrl-C is hit) could could potentially deadlock the runtime system with SMP support.
Own Id: OTP-7104
The sctp driver has been updated to work against newer lksctp packages e.g 1.0.7 that uses the API spelling change adaption -> adaptation. Older lksctp (1.0.6) still work. The erlang API in gen_sctp.erl and inet_sctp.hrl now spells 'adaptation' regardless of the underlying C API.
*** POTENTIAL INCOMPATIBILITY ***
Own Id: OTP-7120
A bug in
Own Id: OTP-7127
The emulator could under rare circumstances crash while garbage collecting.
Own Id: OTP-7132
The documentation has been updated so as to reflect
the last updates of the Erlang shell as well as the minor
modifications of the control sequence
Superfluous empty lines have been removed from code examples and from Erlang shell examples.
Own Id: OTP-6944 Aux Id: OTP-6554, OTP-6911
Bit syntax construction with a small integer in a non-byte aligned field wider than the CPU's word size could cause garbage bits in the beginning of the field.
Own Id: OTP-7085
All Windows versions older than Windows 2000 are now not supported by the Erlang runtime system. This since there was a need for usage of features introduced in Windows 2000.
Own Id: OTP-7086
Memory management improvements especially for the runtime system with SMP support:
If you
for some reason want the memory allocators to be
configured as before, you can pass the
For more
information see the
*** POTENTIAL INCOMPATIBILITY ***
Own Id: OTP-7100
On Unix, denormalized floating point numbers could not be
created using
Own Id: OTP-7122
Native atomic integers and spin-locks are now also available for the runtime system with SMP support on sparc64.
Own Id: OTP-7130
FP exceptions support for sparc64 userspace on Linux has
been added. Note that FP exception support is now turned
off by default, so to actually enable it you need to do
'
Own Id: OTP-7131
A bug for raw files when reading 0 bytes returning 'eof' instead of empty data has been corrected.
Own Id: OTP-6291 Aux Id: OTP-6967
All exported functions in gzio.c have now been renamed to avoid conflict with drivers that are indirectly linked with an external zlib library.
Own Id: OTP-6816 Aux Id: OTP-6591
On the 64-bit Erlang emulator, bit syntax construction with integers containing more than 60 bits ("big numbers") into fields with more than 60 bits could produce incorrect results.
Own Id: OTP-6833
When the runtime system failed to allocate memory for
binaries, it could dead lock while writing the
Own Id: OTP-6848
The runtime system with SMP support could deadlock if a
process called the
Processes suspending each other via the
Own Id: OTP-6920
Processes suspended via
Processes could previously be suspended by one process and resumed by another unless someone was tracing the suspendee. This is not possible anymore. The process resuming a process has to be the one that suspended it.
*** POTENTIAL INCOMPATIBILITY ***
Own Id: OTP-6946
file:write_file/3, file:write/2 and file:read/2 could crash (contrary to documentation) for odd enough file system problems, e.g write to full file system. This bug has now been corrected.
In this process the file module has been rewritten to produce better error codes. Posix error codes now originate from the OS file system calls or are generated only for very similar causes (for example 'enomem' is generated if a memory allocation fails, and 'einval' is generated if the file handle in Erlang is a file handle but currently invalid).
More Erlang-ish error codes are now generated. For
example
The possibility to write
a single byte using
*** POTENTIAL INCOMPATIBILITY ***
Own Id: OTP-6967 Aux Id: OTP-6597 OTP-6291
Monitor messages produced by the system monitor functionality, and garbage collect trace messages could contain erroneous heap and/or stack sizes when the actual heaps and/or stacks were huge.
As of erts version 5.6 the
*** POTENTIAL INCOMPATIBILITY ***
Own Id: OTP-6974 Aux Id: seq10796
Own Id: OTP-7003
The emulator internal process lock implementation has been rewritten and optimized. A slight risk of starvation existed in the previous implementation. This risk has also been eliminated in the new implementation.
Own Id: OTP-6500
Bitstrings (bit-level) binaries and binary comprehensions are now part of the language. See the Reference Manual.
Own Id: OTP-6558
The windows version of erlang now has SMP support. The SMP emulator is run by default on machines which shows more than one virtual or physical processor.
Own Id: OTP-6560 Aux Id: OTP-6925
The details of the compressed term format has been documented in erl_ext_dist.txt. (Thanks to Daniel Goertzen.)
Own Id: OTP-6755
The runtime system with SMP support is now started by
default if more than one logical processor are detected.
For more information, see the
Own Id: OTP-6756
The external format for Erlang terms and the distribution protocol are now documented in ERTS User's Guide.
Own Id: OTP-6779
New BIF's erlang:system_profile/1 and erlang:system_profile/2. These BIF's controls concurrency profiling options for processes, ports and schedulers.
Own Id: OTP-6783 Aux Id: OTP-6285
The
Also the data types
The incorrect data types
For more information see the
Own Id: OTP-6823
Miscellaneous improvements of the erts internal thread library.
It now support optimized atomic operations and spin-locks on windows.
Fall-backs based on mutexes and/or spin-locks for missing optimized atomic operations, spin-locks, or rwlocks has been implemented. This makes it possible to compile the runtime system with SMP support on a lot more platforms.
Default stack size on OpenBSD has been increased to 256 kilo-words.
Own Id: OTP-6831 Aux Id: OTP-6560
Many bit syntax operations, both construction and matching, are faster. For further information, see the Efficiency Guide.
Own Id: OTP-6838
Literal lists, tuples, and binaries are no longer constructed at run-time as they used to be, but are stored in a per-module constant pool. Literals that are used more than once are stored only once.
This is not a change to the language, only in the details of its implementation. Therefore, the implications of this change is described in the Efficiency Guide.
Example 1: In the expression
Example 2: Literal strings, such as
Own Id: OTP-6850
The Erlang driver API has been extended with a portable POSIX thread like API for multi-threading. The Erlang driver thread API provides:
For more
information see the
Own Id: OTP-6857
Recursive calls now usually consume less stack than in R11B. See the Efficiency Guide.
Own Id: OTP-6862 Aux Id: seq10746
The deprecated BIFs
*** POTENTIAL INCOMPATIBILITY ***
Own Id: OTP-6876
Calls to driver call-backs triggered by external events are now scheduled and interleaved with execution of Erlang processes also on the runtime system without SMP support.
Own Id: OTP-6878
Faster arithmetic of integers of more than 27 bits signed (or 60 bits signed on an 64-bit CPU), and also faster integer multiplication. (Thanks to Tony Rogvall.)
Own Id: OTP-6891
Significant improvements of the
For more information see the
Own Id: OTP-6899
Own Id: OTP-6901
Two new guard BIFs have been introduced as a
recommended replacement for
There is also a new
Own Id: OTP-6902
The
The
The
*** POTENTIAL INCOMPATIBILITY ***
Own Id: OTP-6906
As the linux kernel may generate a minor fault when tracing with CPU timestamps, and there exists no patch to the Linux kernel that fixes the problem, cpu timestamps are disabled on Linux for now.
*** POTENTIAL INCOMPATIBILITY ***
Own Id: OTP-6922
The functions io:columns/0, io:columns/1, io:rows/0 and io:rows/1 are added to allow the user to get information about the terminal geometry. The shell takes some advantage of this when formatting output. For regular files and other io-devices where height and width are not applicable, the functions return {error,enotsup}.
Potential incompatibility: If one has written a custom io-handler, the handler has to either return an error or take care of io-requests regarding terminal height and width. Usually that is no problem as io-handlers, as a rule of thumb, should give an error reply when receiving unknown io-requests, instead of crashing.
*** POTENTIAL INCOMPATIBILITY ***
Own Id: OTP-6933
Own Id: OTP-6951
The emulator can now be compiled for 64bit intel, as well as a 32bit universal binary on darwin/MacOSX 10.4 and 10.5.
Own Id: OTP-6961
If
Own Id: OTP-6968
The
Own Id: OTP-6975
On Windows, the werl window now handles resize, so that the whole window can be utilized. Text selection is also updated to be line oriented instead of rectangle oriented as in earlier versions.
Own Id: OTP-6994 Aux Id: OTP-6933
Kqueue support (kernel-poll) has been enabled on FreeBSD. The problem with kqueue not detecting writes on a pipe on FreeBSD was actually not a kqueue issue, but a writev on pipes issue. Neither poll(), nor select() detected the write when the bug hit. NetBSD and DragonFlyBSD probably have or have had the same bug. This bug should have been fixed in FreeBSD 6.3 and FreeBSD 7.0 thanks to Jean-Sebastien Pedron.
Own Id: OTP-7001
Hanging writes on temporarily unavailable NFS filesystems could cause the execution of (not file related) erlang code to get blocked even though I/O threads were used. This is now corrected.
Own Id: OTP-6907 Aux Id: seq10771
Data passed to a driver via
Own Id: OTP-6879
In the SMP emulator, if several processes called ets:update_counter/3 (even for different tables) when the counter values exceeded 27 bits, the counter values could be corrupted or the emulator could crash.
Own Id: OTP-6880 Aux Id: seq10760
Creating a named table using
Turning on call trace on the internal BIF that
implements
SMP emulator only: Using
Own Id: OTP-6872 Aux Id: seq10756, seq10757
ets:select/3 on ordered_set and with a chunksize a multiple of 1000 gave all elements instead of just 1000. Also ets:slot/2 on ordered set could give unexpected results on SMP emulator. Both problems are corrected.
Own Id: OTP-6842
All exported functions in gzio.c have now been renamed to avoid conflict with drivers that are indirectly linked with an external zlib library.
Own Id: OTP-6816 Aux Id: OTP-6591
Calling binary_to_term/1 with certain invalid binaries would crash the emulator.
Own Id: OTP-6817
Restored speed of bit-syntax matching of 32 bits integers.
Own Id: OTP-6789 Aux Id: seq10688
The functions in gzio.c have been renamed to avoid conflict with drivers that indirectly linked with an external zlib library.
Own Id: OTP-6591
The emulator without SMP support dumped core if an
async-thread finished a job after the emulator had begun
writing an
Own Id: OTP-6685
In bit syntax matching, integer fields with greater size than 16Mb would fail to match. (Thanks to Bertil Karlsson and Francesco Pierfederici.)
Matching out a 32-bit integer not aligned on a byte boundary from a binary could cause an heap overflow (and subsequent termination of the emulator).
A module that contained bit syntax construction with a literal field size greater than 16Mb would fail to load.
Several other similar bugs having to do with huge field sizes were eliminated.
Attempting to construct a binary longer than 536870911
bytes will now fail with a
Own Id: OTP-6686
Bugs in rem and div of very large numbers are corrected.
Own Id: OTP-6692
Own Id: OTP-6693
It was previously not possible to pass
A
Own Id: OTP-6699
The
Own Id: OTP-6729
For scripts written using
Own Id: OTP-6593
The section Guards in the chapter The Abstract Format of the ERTS User's Guide has been updated.
Own Id: OTP-6600
Corrected protocol layer flue for socket options SO_LINGER, SO_SNDBUF and SO_RCVBUF, for SCTP.
Own Id: OTP-6625 Aux Id: OTP-6336
The behaviour of the inet option {active,once} on peer close is improved and documented.
Own Id: OTP-6681
The inet option send_timeout for connection oriented sockets is added to allow for timeouts in communicating send requests to the underlying TCP stack.
Own Id: OTP-6684 Aux Id: seq10637 OTP-6681
The command line flag
Own Id: OTP-6697
The
Own Id: OTP-6731
Own Id: OTP-6627 Aux Id: OTP-6160
The minimum and default stack size for async-threads has
been increased to 16 kilowords. This since the previous
minimum and default stack size of 8 kilowords proved to
be too small (introduced in
Own Id: OTP-6628 Aux Id: OTP-6580, Seq10633
process_flag/2 accepts the new flag
Own Id: OTP-6592 Aux Id: seq10555
When a port steals control over a file descriptor from another port, the stealing port tests if the other port is alive. This in order to be able to give an accurate error message. In the runtime system with SMP support, this test was done without appropriate locks held. This could in worst case lead to an erroneous error message; therefore, this bug is to be considered harmless.
Own Id: OTP-6602
The default stack size for threads in the async-thread
pool has been shrunk to 8 kilowords, i.e., 32 KB on
32-bit architectures. This small default size has been
chosen since the amount of async-threads might be quite
large. The default stack size is enough for drivers
delivered with Erlang/OTP, but might not be sufficiently
large for other dynamically linked in drivers that use
the
*** POTENTIAL INCOMPATIBILITY ***
Own Id: OTP-6580
Setting the time on the system while using heart on a linux machine where the emulator was built with clock_gettime support (default from Linux 2.6/erts-5.5.4 and upwards), could make the heart command fire. This was due to bug in the heart executable which is now corrected.
Own Id: OTP-6598 Aux Id: seq10614
Corrected misspelling of '
Own Id: OTP-6433
The MD5 calculation of a BEAM file done by
Own Id: OTP-6459
The emulator could dump core while writing an
Own Id: OTP-6504
Own Id: OTP-6528
A bug in linuxthreads could cause the emulator to dump core when dlerror() was called before the first call to dlopen(). As a workaround the emulator always makes a call to dlopen() on initialization when linuxthreads is used as thread library.
Own Id: OTP-6530
file:sync/1 did not do anything on Windows. Now it calls the system function for flushing buffers (FlushFileBuffers()). (Thanks to Matthew Sackman.)
Own Id: OTP-6531
Own Id: OTP-6536
The file driver (efile_drv) did not flush data written using the option 'delayed_write' after the set timeout time, rather at the next file operation. This bug has now been corrected.
Own Id: OTP-6538
An interface towards the SCTP Socket API Extensions has been implemented.It is an Open Source patch courtesy of Serge Aleynikov and Leonid Timochouk. The Erlang code parts has been adapted by the OTP team, changing the Erlang API somewhat.
The Erlang interface consists of the module
The delivered Open Source patch, before the OTP team rewrites, was written according to http://tools.ietf.org/html/draft-ietf-tsvwg-sctpsocket-13 and was claimed to work fine, tested on Linux Fedora Core 5.0 (kernel 2.6.15-2054 or later) and on Solaris 10 and 11. The OTP team rewrites used the same standard document but might have accidentally broken some functionality. If so it will soon be patched to working state. The tricky parts in C and the general design has essentially not changed. During the rewrites the code was hand tested on SuSE Linux Enterprise Server 10, and briefly on Solaris 10. Feedbach on code and docs is very much appreciated.
The SCTP interface is in beta state. It has only been hand tested and has no automatic test suites in OPT meaning everything is most certainly not tested. Socket active mode is broken. IPv6 is not tested. The documentation has been reworked due to the API changes, but has not been proofread after this.
Thank you from the OTP team to Serge Aleynikov and Leonid Timochouk for a valuable contribution. We hope we have not messed it up too much.
Own Id: OTP-6336
A
Own Id: OTP-6434
There is a new
Own Id: OTP-6505
Setting and getting socket options in a "raw" fashion is now allowed. Using this feature will inevitably produce non portable code, but will allow setting ang getting arbitrary uncommon options on TCP stacks that do have them.
Own Id: OTP-6519
Miscellaneous signal handling improvements on the Erlang runtime system with SMP support.
The fallback implementation of spin locks and atomic operations are now implemented using pthread spin locks when pthread spin locks are found on the system.
The Erlang runtime system with SMP support can now run on
Linux systems that has Linuxthreads instead of NPTL
(Native POSIX Thread Library). Note that the SMP support
hasn't been as thoroughly tested with Linuxthreads as
with NPTL. A runtime system with SMP support will
therefore not be built by default on Linux when NPTL
isn't found. In order to force a build of the runtime
system with SMP support, pass
Own Id: OTP-6525
Own Id: OTP-6431 Aux Id: OTP-6403
The runtime system with SMP support failed to call the driver timeout callback of ports in state closing. This could cause ports to fail flushing their I/O queues.
Own Id: OTP-6432
The
Own Id: OTP-6437
The async id of async jobs created via
Own Id: OTP-6438
Under rare circumstances a terminating connection between two nodes could cause an instantaneous reconnect between the two nodes to fail on the runtime system with SMP support.
Own Id: OTP-6447
In the documentation of the driver entry field
The runtime check for detection of old incompatible drivers made when loading drivers has been improved. The emulator can, however, not make sure that a driver that doesn't use the extended driver interface isn't incompatible. Therefore, when loading a driver that doesn't use the extended driver interface, there is a risk that it will be loaded also when the driver is incompatible. When the driver use the extended driver interface, the emulator can verify that it isn't of an incompatible driver version. You are therefore advised to use the extended driver interface.
For more information see the
Own Id: OTP-6452 Aux Id: OTP-6330
When terminating ports on the runtime system with SMP support, removal of links to processes was done without locking the link lock on processes. This could cause an emulator crash.
Own Id: OTP-6475
The emulator with SMP support could crash when a port
flushed its I/O queue by calling
Own Id: OTP-6479
Large exit reasons could under rare circumstances cause the runtime system with SMP support to crash.
Own Id: OTP-6521
Faster system calls for keeping the time accurate are used on newer Linux kernels, which can result in a significant speed-up of the emulator on those systems.
Own Id: OTP-6430
Added number of async threads and number of scheduler
threads to the system information that can be retrieved
via
Own Id: OTP-6440
When
Own Id: OTP-6465
term_to_binary/2 with compression is now faster.
term_to_binary/2 now accepts the option
'
Future compatibility bugfix: binary_to_term/1 did not
handle the
Own Id: OTP-6494
Removed unnecessary reallocation when initializing kernel-poll set.
Own Id: OTP-6516
Node and fun table entries could under rare circumstances be deallocated multiple times on the emulator with SMP support.
Own Id: OTP-6369
epoll_wait() can repeat entries for the same file descriptor in the result array. This could cause the ready_input, ready_output, or event callbacks of a driver to unintentionally be called multiple times. We have only noted repeated entries when an error condition has occurred on the file descriptor. In this case, the repeated entries should normally not be a problem for the driver since it should detect the error and de-select the file descriptor. Therefore this bug should be considered harmless. The emulator now coalesce repeated entries into one.
You are only affected by this bug if you are using erts-5.5.2.* and the kernel-poll feature on linux.
Own Id: OTP-6376 Aux Id: OTP-6222
If a process that was waiting in gen_tcp:accept/1 was
killed, calling gen_tcp:accept/1 again on the same listen
socket would fail with '
Own Id: OTP-6381 Aux Id: seq10535
The emulator failed to start on Solaris 10 when kernel-poll support was enabled and the maximum number of filedescriptors configured was less than or equal to 256.
Own Id: OTP-6384 Aux Id: OTP-6222
The R10B compiler could generate unsafe
Own Id: OTP-6386
Process and port timers could fail to work properly on the runtime system with SMP support. Many thanks to Dmitriy Kargapolov and Serge Aleynikov who tracked down this bug.
Own Id: OTP-6387
Bit syntax code compiled by an R10B compiler that matched out a floating point number would not properly check that the floating point number was valid; if the float was, for instance, NaN the emulator could crash.
Own Id: OTP-6395
statistics(runtime) on Windows used to return the elapsed system time for the process, instead of the user time. Corrected. (Thanks to Robert Virding.)
Own Id: OTP-6407
A loadable driver (loaded by erl_ddll) which used driver_async() would cause the emulator to crash. (Thanks to Dmitriy Kargapolov.)
Own Id: OTP-6410
Under rare circumstances the emulator on unix platforms
could fail to terminate the Erlang port corresponding to
a port program opened with the
Own Id: OTP-6411
A link removed via
Own Id: OTP-6425 Aux Id: OTP-6160
In the runtime system with SMP support, ports are now being scheduled on the scheduler threads interleaved with processes instead of being run in a separate I/O thread.
Own Id: OTP-6262
More interfaces are added in erl_ddll, to support different usage scenarios.
Own Id: OTP-6307 Aux Id: OTP-6234
In the runtime system with SMP support, the global
I/O lock has been replaced with a more fine grained port
locking scheme. Port locking is either done on driver
level, i.e., all ports executing the same driver share a
lock, or on port level, i.e., each port has its own lock.
Currently the inet driver, the efile driver, and the
spawn driver use port level locking and all other
statically linked in drivers use driver level locking. By
default dynamically linked in drivers will use locking on
driver level. For more information on how to enable port
level locking see the
As of erts
version 5.5.3 the driver interface has been extended. The
extended interface introduce version management, the
possibility to pass capability flags to the runtime
system at driver initialization, and some new driver API
functions. For example, the
NOTE: Dynamically linked in drivers have to be recompiled.
*** POTENTIAL INCOMPATIBILITY ***
Own Id: OTP-6330 Aux Id: OTP-6262
A test and debug feature which modifies the timing of the
runtime system has been added. For more information, see
documentation of the
Own Id: OTP-6382
The version of zlib (http://zlib.net) linked into run-time system has been updated to version 1.2.3.
Own Id: OTP-6394
The
If the
Own Id: OTP-6398
The
A
Own Id: OTP-6403
A port program that had been started with the
Now the emulator doesn't poll for termination of the port program at all; instead, it waits for the child signal from the terminated port program to arrive and then schedules the Erlang port for termination.
The termination of any port programs have also been
optimized. Previously the termination of any port program
did always cause a scan of a table of the size equal to
maximum number of file descriptors. If the maximum number
of file descriptors was large, this scan could be quite
expensive. Now the search have been reduced to the set of
ports started with the
Note, all of the above only applies to Erlang emulators on Unix platforms.
Own Id: OTP-6412 Aux Id: seq10194
* BEAM: added support for floating-point exceptions on FreeBSD (32-bit x86)
* SMP: made locking procedures work even when native lock operations aren't implemented
* SMP: improved timing accuracy in the timer thread (if enabled)
Own Id: OTP-6424
A bug in the kernel poll implementation could cause the emulator to omit polling for events on file descriptors. The bug was only present when using the kernel poll implementation based on epoll or kqueue. This bug was introduced in erts-5.5.2.
Own Id: OTP-6344 Aux Id: OTP-6222
The run_erl program now acquires its pseudo-ttys using openpty(3), so that it will work on newer Linux distributions that don't have the traditional pseudo-tty devices in the file system. On platforms that don't have openpty(3), run_erl will still search for pseudo-tty devices in the file system.
The run_erl program will now wait using waitpid(3) to prevent the program it spawned to become defunct. run_erl will also terminate after a delay of 5 seconds (to allow any pending output to be written to the log file) if the spawned program terminates even if some child of it still holds stdin and/or stdout open.
Own Id: OTP-6225 Aux Id: seq10500
A bug in ordered_set ETS datatyp caused ets:select (and match) to return faulty results when the table contained process id's from another node.
Own Id: OTP-6338
erlc: A typo in the help text for '-pa path' was corrected.
Own Id: OTP-6218
Failure in port command/control driver callbacks could crash the non-SMP emulator. This bug was introduced in the 5.5 version of erts.
Own Id: OTP-6224
Erroneous "
Own Id: OTP-6229 Aux Id: OTP-3993, Seq5266, Seq7247, OTP-4307
The emulator could cause a type assertion failure while writing an erl_crash.dump, causing the erl_crash.dump to be terminated and a core dump generated.
Own Id: OTP-6235 Aux Id: seq10444
The registered name of a process is now the last observable resource removed before links and monitors are triggered when a process terminates.
Previously ets tables were removed after the registered name. This could cause problems on the runtime system with SMP support for code that expected that ets tables owned by a specific process had been removed if the name of the process had been removed.
Own Id: OTP-6237
Failure to fork() a new (os) process could cause the emulator to deadlock. This bug affect all emulators with SMP support, and emulators with async thread support on SunOS.
Own Id: OTP-6241 Aux Id: OTP-3906
Fprof traces could become truncated for the SMP emulator. This bug has now been corrected.
Own Id: OTP-6246
The undocumented functions inet:getiflist/0,1 inet:ifget/2,3 and inet:getif/1 were completely broken on Windows. That has been fixed.
Own Id: OTP-6255
Behavior in case of disappeared nodes when using the dist_auto_connect once got changed in R11B-1. The timeouts regarding normal distributed operations is now reverted to the old (pre R11B-1).
Own Id: OTP-6258 Aux Id: OTP-6200, seq10449
The bsl and bsr operators could cause the emulator to crash if given invalid arguments. (Thanks to datacompboy and Per Gustafsson.)
Own Id: OTP-6259
driver_cancel_timer() could under certain circumstances fail to cancel the timer on the runtime system with SMP support.
Own Id: OTP-6261
A call to erlang:system_info(info) could deadlock the runtime system with SMP support.
Own Id: OTP-6268
Exit signals are now truly asynchronous in the runtime system with SMP support. This simplifies locking in bifs a lot, and makes process termination cheaper.
Own Id: OTP-6160
When tracing on the runtime system with SMP support it
can be difficult to know when a trace has been delivered
to the tracer. A new built in function
Own Id: OTP-6205 Aux Id: OTP-6269
Kernel poll support can now be combined with SMP support.
Currently the following kernel poll versions exist:
The "check io" implementation for unix has been completely rewritten. The current kernel poll implementation reduce the amount of system calls needed compared to the old kernel poll implementation.
When
Kernel poll support is now enabled by default if
Note:
Own Id: OTP-6222 Aux Id: seq10380
The
Own Id: OTP-6234
The SMP emulator now avoids locking for the following
operations (thus making them as fast as in the UP
emulator):
Own Id: OTP-6252
There are new BIFs
The
Own Id: OTP-6281
There is now an option read_packets for UDP sockets that sets the maximum number of UDP packets that will be read for each invocation of the socket driver.
Own Id: OTP-6249 Aux Id: seq10452
Complex pattern matching of strings would fail in the 64 bits emulator because of a bug in the loader. (Thanks to Igor Goryachev.)
Own Id: OTP-6142
Own Id: OTP-6154
erlang:display/1 displayed erroneous values for negative integers.
Big integers (both positive and negative) were previously displayed in hexadecimal form while small integers were displayed in decimal form. All integers are now displayed in decimal form.
NOTE: erlang:display/1 should only be used for debugging.
Own Id: OTP-6156
A call to erlang:trace/3 with erroneous flags caused the SMP emulator to deadlock instead of exiting the calling process with badarg.
Own Id: OTP-6175
A bug causing the emulator to hang when exiting a process that is exception traced has been fixed.
Own Id: OTP-6180
ets:rename/1 could deadlock, or crash the SMP emulator when the table wasn't a named table.
ets:next/2, and ets:prev/2 could return erroneous results on the SMP emulator.
Own Id: OTP-6198 Aux Id: seq10392, seq10415
A memory allocation bug could cause the SMP emulator to
crash when a process had executed a
Own Id: OTP-6199
The runtime system with SMP support did not slowly adjust its view of time when the system time suddenly changed.
Timeouts could sometimes timeout too early on the runtime system with SMP support.
Own Id: OTP-6202
The smp runtime system now automatically detects the number of logical processors on MacOSX (darwin) and OpenBSD.
The smp runtime system is now built by default on MacOSX (darwin) on x86.
Own Id: OTP-6119
The
Especially the
Own Id: OTP-6126
Increased the reduction cost for sending messages in the SMP emulator so it behaves more like the non-SMP emulator.
Own Id: OTP-6196
A port running a dynamically linked-in driver that exits
due to the driver being unloaded now exits with exit
reason
*** POTENTIAL INCOMPATIBILITY ***
Own Id: OTP-6204
Changed name of the
*** POTENTIAL INCOMPATIBILITY ***
Own Id: OTP-6208
The changes below were made by Mikael Pettersson, HiPE.
HiPE runtime system:
Reduce overheads in the HiPE runtime system's BIF glue code.
Fix bug when exceptions are thrown from BEAM to HiPE.
Support SPARC on Linux.
Support x86 on FreeBSD.
Floating-point exceptions:
Reduce overheads in checking results of floating-point operations.
Minor bug fix in SSE2 floating-point exception handling.
Support SSE2 floating-point exceptions on 32-bit x86 machines.
Make FP exceptions work in the SMP runtime system on FreeBSD/x86.
Support floating-point exceptions on SPARCs running Linux.
Runtime system:
Minor scheduler optimisation in the non-SMP runtime system.
Substantial reduction of I/O thread overheads in the SMP runtime system if the separate timer thread is used. (In R11B-1, the separate timer thread is not used.)
Own Id: OTP-6211
Previously
The new behavior of
NOTE: This change can cause some obscure code to fail which previously did not. For example, the following code might hang:
ok
%% We were previously guaranteed to get a down message
%% (since we exited the process ourself), so we could
%% in this case leave out:
%% after 0 -> ok
end,
]]>
*** POTENTIAL INCOMPATIBILITY ***
Own Id: OTP-5772
Two bugs fixed: If the environment variable
Own Id: OTP-6054
The documentation for writing drivers in the ERTS User's Guide has been expanded and updated.
Own Id: OTP-5192
The
Own Id: OTP-5894 Aux Id: OTP-5149
There is a new trace match spec function
The
Own Id: OTP-5956
Erlang runtime system with SMP (symmetric multi processing) support.
The runtime system with SMP support is in this release focused on stability and there are a number of steps with optimizations to follow before it will take full advantage of multi processor systems. The released system is however truly multi threaded and you will notice increased performance for many applications already. We recommend that you evaluate your application on the SMP version of the runtime system and wait for some more optimizations before you use it in a real product. You will then discover if there are any problems in your application that needs to be fixed in order for it to work properly in a multi threaded environment. More optimized versions of the runtime system with SMP support will be included in the R11B maintenance releases.
The SMP enabled runtime system will be started if
the
A runtime system with SMP support is by default built on the following platforms if posix threads, and a gcc compiler of at least version 2.95 is found:
Linux with at least kernel version 2.6 and the Native POSIX Thread Library on x86, x86_64, and 32-bits PowerPC.
Solaris of at least version 8 on 32-bits SPARC-V9.
MacOSX of at least version 10.4 (Darwin 8.0) on 32-bits PowerPC.
The runtime system with SMP support is known not to build on:
Windows.
Linux with kernel versions less than 2.4, or without the Native POSIX Thread Library.
Other hardware platforms than x86, x86_64, 32-bits SPARC-V9 and 32-bits PowerPC.
Windows will be supported in a future release.
The runtime system with SMP support might build on other
operating systems in combination with supported hardware.
In order to force a build of a runtime system with SMP
support, pass the
NOTE: The design of SMP support for drivers is ongoing. There will probably be incompatible driver changes (only affecting drivers run on the runtime system with SMP support) released as patches for R11B.
Potential incompatibility: Previously, specific driver call-backs were always called from the same thread. This is not true in the runtime system with SMP support. Calls to call-backs will be made from different threads, e.g., two consecutive calls to exactly the same call-back can be made from two different threads. This will in most cases not be a problem. All calls to call-backs are synchronized, i.e., only one call-back will be called at a time.
In the future the default behavior will probably be the following: Calls to call-backs will, as now, be made from different threads. Calls to call-backs in the same driver instance will be synchronized. It will probably be possible to configure so that all calls to call-backs in all driver instances of a specific driver type will be synchronized. It may be possible to configure so that all calls to call-backs of a driver instance or a of a specific driver type will be made from the same thread.
Parallelism in the Erlang code executed is a necessity for the Erlang runtime system to be able to take advantage of multi-core or multi-processor hardware. There need to be at least as many Erlang processes runnable as processor cores for the Erlang runtime system to be able to take advantage of all processor cores.
An Erlang runtime system with SMP support with only one Erlang process runnable all the time will almost always be slower than the same Erlang runtime system without SMP support. This is due to thread synchronization overhead.
Known major bottleneck in the Erlang runtime system:
Currently the I/O system uses one "big lock", i.e. only one thread can do I/O at a time (with the exception of async threads and threads created by users own linked-in drivers). This is high on the list of things to optimize. Note, code that does not do I/O can be executed at the same time as one thread does I/O.
Some pitfalls which might cause Erlang programs that work on the non-SMP runtime system to fail on the SMP runtime system:
A newly spawned process will often begin executing immediately. Code that expects that the parent process will be able to execute for a while before the child process begins executing is likely to fail.
High priority processes could previously provide mutual exclusion (bad programming style) by preventing normal and low priority processes from being run. High priority processes cannot be used this way to provide mutual exclusion.
Obscure pitfall, only if a process being traced also
sends normal messages to the tracer:
The order between trace messages and normal
messages is undefined. I.e. the order between normal
messages sent from a tracee to a tracer and the trace
messages generated from the same tracee to the same
tracer is undefined. The internal order of normal
messages and the internal order of trace messages will,
of course, be preserved as before.
The kernel poll feature is currently not supported by the runtime system with SMP support. It will probably be supported in a future release.
*** POTENTIAL INCOMPATIBILITY ***
Own Id: OTP-6006 Aux Id: OTP-6095
Linked-in driver modifications.
Linked-in drivers must be recompiled.
The
*** POTENTIAL INCOMPATIBILITY ***
Own Id: OTP-6095 Aux Id: OTP-6006
Large files (more than 2 GBytes) are now handled on Solaris 8.
Own Id: OTP-5849 Aux Id: seq10157
A failing bit syntax construction could fail with the
PREVIOUS exception reason that had occurred in the process
(instead of with
Own Id: OTP-5911
When building OTP, the Kernel application was built in both the primary and secondary bootstrap steps, which would cause problems if OTP including its bootstrap is checked into a version control system (such as CVS). (Thanks to Sebastian Strollo.)
Own Id: OTP-5921
Own Id: OTP-5933
Own Id: OTP-5940
Execution of match specs could under rare circumstances cause the emulator to dump core.
Execution of match specs could cause memory leaks in the hybrid emulator.
Own Id: OTP-5955
A bug in
Own Id: OTP-5957
Different (and old)
Own Id: OTP-5967
pthread header and library mismatch on Linux systems (at least some SuSE and Debian) with both NPTL and Linuxthreads libraries installed.
Own Id: OTP-5981
The driver_set_timer did not change the previous timeout if called a second time. Now it works as specified, changing the timeout.
Own Id: OTP-5942
The undocumented
Own Id: OTP-5945
The setuid_socket_wrap program was corrected to work for
C compilers that treat the
Own Id: OTP-5946
Fixed a minor build problem on Windows.
Own Id: OTP-5819 Aux Id: OTP-5382 OTP-5540 OTP-5577
The
Own Id: OTP-5822
If there were user-defined variables in the boot
script, and their values were not provided using the
The
Own Id: OTP-5828 Aux Id: seq10151
The HiPE compiler identifies more leaf functions, giving slightly faster code.
Corrected problems in HiPE's coalescing register allocating that would cause it to fail when compiling very large functions (e.g. some of parse modules in the Megaco application).
Own Id: OTP-5853
Timers could sometimes timeout too early. This bug has now been fixed.
Automatic cancellation of timers created by
In order to be able to maintain a larger amount of timers without increasing the maintenance cost, the internal timer wheel and bif timer table have been enlarged.
Also a number of minor bif timer optimizations have been implemented.
Own Id: OTP-5795 Aux Id: OTP-5090, seq8913, seq10139, OTP-5782
Own Id: OTP-5827
By setting Unix environment variables, the priority for
the emulator can be lowered when it is writing crash
dumps and the time allowed for finishing writing a crash
dump can be set to a certain number of seconds. See the
documentation for
Own Id: OTP-5818
Documentation improvements:
- documentation for
- command line flag
-
-
Own Id: OTP-5847
-D_GNU_SOURCE is now always passed on the compile command line on linux. This in order to ensure that all included system headers see _GNU_SOURCE defined.
_GNU_SOURCE is now also defined on linux in configure when looking for features.
Some minor (harmless) configure bugs were also fixed.
Own Id: OTP-5749
Some compiler warnings and Dialyzer warnings were eliminated in the Tools application.
When tracing to a port (which
Own Id: OTP-5757
The BIFs
The BIF
Minor bug fix: The exception reason could be changed
to
Minor bugfix: On Windows,
The message in the documentation for
Own Id: OTP-5709 Aux Id: seq10100
The previously undocumented and UNSUPPORTED
*** POTENTIAL INCOMPATIBILITY ***
Own Id: OTP-5715
New socket options
Own Id: OTP-5756
Only the emulator is now linked with termcap library in order to decrease library dependencies for other otp programs.
Own Id: OTP-5758
The native resolver has gotten an control API for
extended debugging and soft restart. It is:
Own Id: OTP-5751 Aux Id: EABln25013
On VxWorks, epmd did not handle file descriptors with higher numbers than 63. Also, if epmd should get a file descriptor with a number >= FD_SETSIZE, it will close a the file descriptor and write a message to the log (instead of mysteriously fail); the Erlang node that tried to register will fail with a duplicate_name error (unfortunately, epmd has no way to indicate to the Erlang node why the register attempt failed).
Own Id: OTP-5716 Aux Id: seq10070
Timezone data is now initialized better. (was a problem at least on NetBSD 2.0.2) Thanks to Rich Neswold.
Own Id: OTP-5621
The hybrid-heap emulator ('erl -hybrid') is much more stable. We have corrected all known bugs that caused it to dump core while running our test suites.
Own Id: OTP-5634
Fixed rare memory leaks in
Own Id: OTP-5692
Processes were sometimes unnecessarily garbage collected when terminating. These unnecessary garbage collections have now been eliminated.
Own Id: OTP-5693
The
The
Own Id: OTP-5645 Aux Id: seq9984
The term-building driver functions
The ERL_DRV_FLOAT type has been added.
For the ERL_DRV_BINARY type, the length and offset are now validated against the length of the driver binary.
The ERL_DRV_PID type is now implemented (it was documented, but not implemented).
Own Id: OTP-5674
Own Id: OTP-5572
A bug regarding tcp sockets which results in hanging
Corrected a bug in the (undocumented and unsupported)
option
Updated the documentation regarding the second argument to
Own Id: OTP-5582 Aux Id: seq9839
Erlang/OTP will now build on Mac OS X 10.4 "Tiger" (the problem was that 10.4 has a partially implemented poll() function that can't handle devices). Also, on Mac OS X 10.3 "Panther", Erlang/OTP will now use select() instead of poll() (because poll() on Mac OS X 10.3 is implemented using select()).
Own Id: OTP-5595
A bug in the file driver when opening a file in
compressed mode, and the returned allocated pointer from
the compressing library was in very high memory (>= 2GB),
causing e.g.
Own Id: OTP-5618
The new fun
The new type test
Own Id: OTP-5584
In the HiPE application, there's a new experimental register allocator (optimistic coalescing), and the linear scan register allocator is now also available on ppc. Plus lots of cleanups.
Minor hybrid heap corrections.
The maximum size of a heap used to be artificially limited so that the size of a heap would fit in 28 bits; that limitation could cause the emulator to terminate in a garbage collection even if there still was available memory. Now the largest heap size for a 32 bit CPU is 1,699,221,830 bytes. (Thanks to Jesper Wilhelmsson.)
Also removed the undocumented
Own Id: OTP-5596
Own Id: OTP-5561
The
Own Id: OTP-5532 Aux Id: seq9813
The last known
Own Id: OTP-5544 Aux Id: OTP-5522
Some math libraries do not always throw floating-point exceptions on errors. In order to be able to use these libraries, floating-point errors are now more thoroughly checked.
Misc floating-point fixes for Linux and MacOSX.
Own Id: OTP-5467
An internal buffer was sometimes not cleared which caused garbage to appear in error messages sent to the error logger.
Only emulators on unix platforms were affected by these bugs.
Own Id: OTP-5492
The ethread library now works on OpenBSD.
Own Id: OTP-5515
Corrected a bug in the (undocumented and unsupported)
option
Own Id: OTP-5519
Own Id: OTP-5484 Aux Id: seq9801
Some more stability problems were fixed in the hybrid-heap emulator.
Own Id: OTP-5489
After
Own Id: OTP-5522
If a process had node links (created by
Own Id: OTP-5420
Minor corrections to the help text printed by
Own Id: OTP-5428
32-bit words were used for offsets in the garbage collector. This caused the emulator to crash on 64-bit machines when heaps were moved more than 4 GB during garbage collection.
Own Id: OTP-5430
Own Id: OTP-5448
If there was a call to
Own Id: OTP-5450 Aux Id: seq9722
The
Own Id: OTP-5388
The function
Own Id: OTP-5297 Aux Id: OTP-4927
The
Own Id: OTP-5324 Aux Id: seq9698
In the 'bag' type of ets tables, elements having the same key were supposed to be order in insertion order. The would be wrong if a rehash occurred.
Own Id: OTP-5340 Aux Id: seq9704
Linked in drivers in the Crypto and Asn1 applications
are now compiled with the
Linked in drivers on MacOSX are not compiled with the
undocumented
Linked in driver in Crypto, and port programs in SSL, now compiles on OSF1.
Minor makefile improvements in Runtime_Tools.
Own Id: OTP-5346
Fixed a bug in the hybrid heap in distributed send operations.
Own Id: OTP-5361
A BIF
Own Id: OTP-5376 Aux Id: OTP-5257
Mikael Pettersson (HiPE) corrected a few bugs in the emulator that caused problems when compiled with the experimental gcc-4.0.0.
Own Id: OTP-5386
Minor update of the internal documentation of
the
The listen port of
Own Id: OTP-5234
Own Id: OTP-5384
A few bugs were corrected in the HiPE application.
Own Id: OTP-5385
Font and color preferences for
Own Id: OTP-5250
OTP archive libraries, e.g. the
Own Id: OTP-5274
Bugs in
Own Id: OTP-5292
Corrected a crash in the 64-bits emulator.
Corrected a problem in the hybrid heap emulator.
In the chapter about the abstract format in the ERTS User's Guide, updated the last section about how the abstract format is stored in BEAM files.
Own Id: OTP-5262
The maximum number of concurrent threads in the internal ethread thread package has been limited to 2048.
Own Id: OTP-5280
If Erlang/OTP was installed in a short directory name,
such as
Own Id: OTP-5254
If one used
Own Id: OTP-5209 Aux Id: seq9198
Arithmetic with big numbers could crash the emulator.
The HiPE native code compiler and run-time code in the emulator has been updated. (Note: Native code is still not supported.)
Eliminated a few bugs that could crash the hybrid emulator (which is not supported).
Own Id: OTP-5233 Aux Id: seq9587
The ethread library was unnecessarily rebuilt multiple times during the build process, also a debug version of the library was build during the install phase. These unnecessary builds have now been removed. Note, the content of the installed Erlang/OTP system is not effected at all by this change.
Own Id: OTP-5203
The emulator could fail to clear the memory segment cache. This could potentially cause memory allocation to unnecessarily fail when memory usage was close to its maximum. This bug has now been fixed.
Own Id: OTP-5211
std_alloc (std short for standard) was sometimes called def_alloc (def short for default). std_alloc is now everywhere referred to as std_alloc.
Own Id: OTP-5216
A documentation bug has been corrected in
the
Own Id: OTP-5217
The emulator now close all open files and sockets
immediately after receiving an USR1 signal. This causes
the emulator to unregister at
Own Id: OTP-5221 Aux Id: OTP-4985, seq9514
Try/catch support in the emulator slightly updated.
Own Id: OTP-5229