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2015-04-15Raise more descriptive error messages for failed map operationsBjörn Gustavsson
According to EEP-43 for maps, a 'badmap' exception should be generated when an attempt is made to update non-map term such as: <<>>#{a=>42} That was not implemented in the OTP 17. José Valim suggested that we should take the opportunity to improve the errors coming from map operations: http://erlang.org/pipermail/erlang-questions/2015-February/083588.html This commit implement better errors from map operations similar to his suggestion. When a map update operation (Map#{...}) or a BIF that expects a map is given a non-map term, the exception will be: {badmap,Term} This kind of exception is similar to the {badfun,Term} exception from operations that expect a fun. When a map operation requires a key that is not present in a map, the following exception will be raised: {badkey,Key} José Valim suggested that the exception should be {badkey,Key,Map}. We decided not to do that because the map could potentially be huge and cause problems if the error propagated through links to other processes. For BIFs, it could be argued that the exceptions could be simply 'badmap' and 'badkey', because the bad map and bad key can be found in the argument list for the BIF in the stack backtrace. However, for the map update operation (Map#{...}), the bad map or bad key will not be included in the stack backtrace, so that information must be included in the exception reason itself. For consistency, the BIFs should raise the same exceptions as update operation. If more than one key is missing, it is undefined which of keys that will be reported in the {badkey,Key} exception.
2015-03-20Merge branch 'rickard/time_api/OTP-11997'Rickard Green
* rickard/time_api/OTP-11997: (22 commits) Update primary bootstrap inets: Suppress deprecated warning on erlang:now/0 inets: Cleanup of multiple copies of functions Add inets_lib with common functions used by multiple modules inets: Update comments Suppress deprecated warning on erlang:now/0 Use new time API and be back-compatible in inets Remove unused functions and removed redundant test asn1 test SUITE: Eliminate use of now/0 Disable deprecated warning on erlang:now/0 in diameter_lib Use new time API and be back-compatible in ssh Replace all calls to now/0 in CT with new time API functions test_server: Replace usage of erlang:now() with usage of new API Replace usage of erlang:now() with usage of new API Replace usage of erlang:now() with usage of new API Replace usage of erlang:now() with usage of new API Replace usage of erlang:now() with usage of new API otp_SUITE: Warn for calls to erlang:now/0 Replace usage of erlang:now() with usage of new API Multiple timer wheels Erlang based BIF timer implementation for scalability Implement ethread events with timeout ... Conflicts: bootstrap/bin/start.boot bootstrap/bin/start_clean.boot bootstrap/lib/compiler/ebin/beam_asm.beam bootstrap/lib/compiler/ebin/compile.beam bootstrap/lib/kernel/ebin/auth.beam bootstrap/lib/kernel/ebin/dist_util.beam bootstrap/lib/kernel/ebin/global.beam bootstrap/lib/kernel/ebin/hipe_unified_loader.beam bootstrap/lib/kernel/ebin/inet_db.beam bootstrap/lib/kernel/ebin/inet_dns.beam bootstrap/lib/kernel/ebin/inet_res.beam bootstrap/lib/kernel/ebin/os.beam bootstrap/lib/kernel/ebin/pg2.beam bootstrap/lib/stdlib/ebin/dets.beam bootstrap/lib/stdlib/ebin/dets_utils.beam bootstrap/lib/stdlib/ebin/erl_tar.beam bootstrap/lib/stdlib/ebin/escript.beam bootstrap/lib/stdlib/ebin/file_sorter.beam bootstrap/lib/stdlib/ebin/otp_internal.beam bootstrap/lib/stdlib/ebin/qlc.beam bootstrap/lib/stdlib/ebin/random.beam bootstrap/lib/stdlib/ebin/supervisor.beam bootstrap/lib/stdlib/ebin/timer.beam erts/aclocal.m4 erts/emulator/beam/bif.c erts/emulator/beam/erl_bif_info.c erts/emulator/beam/erl_db_hash.c erts/emulator/beam/erl_init.c erts/emulator/beam/erl_process.h erts/emulator/beam/erl_thr_progress.c erts/emulator/beam/utils.c erts/emulator/sys/unix/sys.c erts/preloaded/ebin/erlang.beam erts/preloaded/ebin/erts_internal.beam erts/preloaded/ebin/init.beam erts/preloaded/src/erts_internal.erl lib/common_test/test/ct_hooks_SUITE_data/cth/tests/empty_cth.erl lib/diameter/src/base/diameter_lib.erl lib/kernel/src/os.erl lib/ssh/test/ssh_basic_SUITE.erl system/doc/efficiency_guide/advanced.xml
2015-03-20Erlang based BIF timer implementation for scalabilityRickard Green
2015-03-20Introduce a new time APIRickard Green
The old time API is based on erlang:now/0. The major issue with erlang:now/0 is that it was intended to be used for so many unrelated things. This tied these unrelated operations together and unnecessarily caused performance, scalability as well as accuracy, and precision issues for operations that do not need to have such issues. The new API spreads different functionality over multiple functions in order to improve on this. The new API consists of a number of new BIFs: - erlang:convert_time_unit/3 - erlang:monotonic_time/0 - erlang:monotonic_time/1 - erlang:system_time/0 - erlang:system_time/1 - erlang:time_offset/0 - erlang:time_offset/1 - erlang:timestamp/0 - erlang:unique_integer/0 - erlang:unique_integer/1 - os:system_time/0 - os:system_time/1 and a number of extensions of existing BIFs: - erlang:monitor(time_offset, clock_service) - erlang:system_flag(time_offset, finalize) - erlang:system_info(os_monotonic_time_source) - erlang:system_info(time_offset) - erlang:system_info(time_warp_mode) - erlang:system_info(time_correction) - erlang:system_info(start_time) See the "Time and Time Correction in Erlang" chapter of the ERTS User's Guide for more information.
2014-11-03Merge branch 'sverk/yielding-distr-send/OTP-12232'Sverker Eriksson
* sverk/yielding-distr-send/OTP-12232: erts: Add constant TERM_TO_BINARY_MEMCPY_FACTOR erts: Optimize some repeated calls to {E,W}STACK_PUSH erts: Yield in term_to_binary when encoding big maps erts: Remove unnecessary goto for fun encoding erts: Yield in term_to_binary while copying large binaries erts: Implement yielding for distributed send of large messages
2014-08-29erts: Implement yielding for distributed send of large messagesSverker Eriksson
Use same mechanism as term_to_binary to yield while encoding large messages for distributed send.
2014-06-06Merge branch 'maint'Rickard Green
2014-05-22Make binary BIFs converting from lists yield on large inputRickard Green
- erlang:list_to_binary/1 - erlang:iolist_to_binary/1 - erlang:list_to_bitstring/1 - binary:list_to_bin/1
2014-05-22Make binary BIFs converting to lists yield on large inputRickard Green
- erlang:binary_to_list/1 - erlang:binary_to_list/3 - erlang:bitstring_to_list/1
2014-05-14Remove obsolete 'imports' entry from module_info/1/2 functionsRichard Carlsson
It previously always returned an empty list and was documented to be removed.
2014-05-14Add 'md5' entry for module_info/0/1 functions.Richard Carlsson
2014-02-24further enhancements for dirty schedulersSteve Vinoski
Add support for setting the number of dirty CPU schedulers online via erlang:system_flag/2. Assuming the emulator is built with dirty schedulers enabled, the number of dirty CPU schedulers online may not be less than 1, nor greater than the number of dirty CPU schedulers available, nor greater than the number of normal schedulers online. Dirty CPU scheduler threads that are taken offline via system_flag/2 are suspended. The number of dirty CPU schedulers online may be adjusted independently of the number of normal schedulers online, but if system_flag/2 is used to set the number of normal schedulers online to a value less than the current number of normal schedulers online, the number of dirty CPU schedulers online is decreased proportionally. Likewise, if the number of normal schedulers online is increased, the number of dirty CPU schedulers online is increased proportionally. For example, if 8 normal schedulers and 4 dirty CPU schedulers are online, and system_flag/2 is called to set the number of normal schedulers online to 4, the number of dirty CPU schedulers online is also decreased by half, to 2. Subsequently setting the number of normal schedulers online back to 8 also sets the number of dirty CPU schedulers online back to 4. Augment the system_flag/2 documentation in the erlang man page to explain this relationship between schedulers_online and dirty_cpu_schedulers_online. Also ensure that all dirty CPU and I/O schedulers are suspended when multi-scheduling is blocked via system_flag/2, and brought back online when multi-scheduling is unblocked. Add Rickard Green's rewritten check_enqueue_in_prio_queue() function that inspects process state more thoroughly to determine if to enqueue it and if so on what queue, including dirty queues when appropriate. Make sure dirty NIF jobs do not trigger erlang:system_monitor long_schedule messages. Add more dirty scheduler testing to the scheduler test suite. Remove the erts_no_dirty_cpu_schedulers_online global variable, since it's no longer needed. Execute dirty NIFs on a normal scheduler thread while multi-scheduling blocking is in effect. Evacuate any dirty jobs residing in the dirty run queues over to a normal run queue when multi-scheduling is blocked. Allow dirty schedulers to execute aux work. Set the dirty run queues halt_in_progress flag when halting the normal schedulers. Change dirty scheduler numbers to a structure including both scheduler number and type, either dirty CPU or dirty I/O. Add some assertions to ensure that dirty CPU schedulers operate only on dirty CPU scheduler process flags, and the same for dirty I/O schedulers.
2013-12-17Merge tag 'OTP_R16B03_yielding_binary_to_term'Sverker Eriksson
Yielding binary_to_term. OTP-11535 * tag 'OTP_R16B03_yielding_binary_to_term': Increase versions for OTP_R16B03_yielding_binary_to_term erts: Adjust term_to_binary reduction factors erts: Yield after trapping term_to_binary if gc has been ordered erts: Let term_to_binary disable gc while trapping erts: Improve stress of binary_to_term in binary_SUITE erts: Fix bug in binary_to_term for compressed on halfword erts: Fix crash when binary_to_term throws badarg erts: Trapping memcpy in binary_to_term erts: Cleanup code for trapping binary_to_term erts: Add erlang wrappers to binary_to_term trapping uncompress trapping size calculation trapping binary_to_term/2 trapping STRING_EXT trapping lists and tuples trapping binary_to_term passing binary_SUITE Conflicts: erts/preloaded/ebin/erlang.beam erts/preloaded/ebin/erts_internal.beam erts/vsn.mk lib/kernel/vsn.mk lib/stdlib/vsn.mk
2013-12-07Merge branch 'rickard/garbage_collect/OTP-11388'Rickard Green
* rickard/garbage_collect/OTP-11388: Parallel check_process_code when code_server purge a module Functionality for disabling garbage collection Use asynchronous check_process_code in code_parallel_SUITE Execution of system tasks in context of another process Conflicts: bootstrap/lib/kernel/ebin/hipe_unified_loader.beam erts/preloaded/ebin/erlang.beam erts/preloaded/ebin/erts_internal.beam
2013-11-18trapping binary_to_term passing binary_SUITESverker Eriksson
2013-11-18Execution of system tasks in context of another processRickard Green
A process requesting a system task to be executed in the context of another process will be notified by a message when the task has executed. This message will be on the form: {RequestType, RequestId, Pid, Result}. A process requesting a system task to be executed can set priority on the system task. The requester typically set the same priority on the task as its own process priority, and by this avoiding priority inversion. A request for execution of a system task is made by calling the statically linked in NIF erts_internal:request_system_task(Pid, Prio, Request). This is an undocumented ERTS internal function that should remain so. It should *only* be called from BIF implementations. Currently defined system tasks are: * garbage_collect * check_process_code Further system tasks can and will be implemented in the future. The erlang:garbage_collect/[1,2] and erlang:check_process_code/[2,3] BIFs are now implemented using system tasks. Both the 'garbage_collect' and the 'check_process_code' operations perform or may perform garbage_collections. By doing these via the system task functionality all garbage collect operations in the system will be performed solely in the context of the process being garbage collected. This makes it possible to later implement functionality for disabling garbage collection of a process over context switches. Newly introduced BIFs: * erlang:garbage_collect/2 - The new second argument is an option list. Introduced option: * {async, RequestId} - making it possible for users to issue asynchronous garbage collect requests. * erlang:check_process_code/3 - The new third argument is an option list. Introduced options: * {async, RequestId} - making it possible for users to issue asynchronous check process code requests. * {allow_gc, boolean()} - making it possible to issue requests that aren't allowed to garbage collect (operation will abort if gc should be needed). These options have been introduced as a preparation for parallelization of check_process_code operations when the code_server is about to purge a module.
2013-08-16Merge branch 'pan/update_pcre_8.33'Patrik Nyblom
* pan/update_pcre_8.33: Workaround TR gnu/181328, GCC 4.2.1 20070831 on FreeBSD 9.1 Clarify relation between erts_iolist_{size|to_buf} Fix backslash in titles of manpages Correct UTF-8 in stdlib's notes.xml Add more tests for corner error cases in erl_bif_re.c Add documentation of report_errors and match_limit(_recursion) Add match_limit and match_limit_recursion options Add return_errors option to re:run/3 Add README for updating PCRE Add documentation of extensions to re module Add new options to Erlang re interface and mend dupnames Update PCRE doc part of re.xml to PCRE 8.33 state Integrate new PCRE test suites Integrate patch for PCRE bug id 1370 Handle CRLF correctly in global regexp Add erts_prefix to pcre_library and update erl_bif_re Update to PCRE 8.33, w/o the erts_ prefix added OTP-11204 OTP-11205 OTP-10285
2013-08-09Add return_errors option to re:run/3Patrik Nyblom
2013-08-09Add new options to Erlang re interface and mend dupnamesPatrik Nyblom
Add notempty_atstart, no_start_optimize, ucp and never_utf options from new PCRE version. Use the new notempty_atstart in global matching. Add inspect/2 function Correctly handle dupnames when capturing a name, as in Perl, get the leftmost matching occurence. Also added all_names, to get all the names in the pattern in alphabetical (name) order. To be able to use this in global matching, an inspect function that can dig out a namelist was added.
2013-07-11erts: Add cflags, ldflags and config.h into executableLukas Larsson
2013-06-11Merge branch 'pan/happi/yield_in_term_to_binary' into maintOTP_R16B01_RC1Patrik Nyblom
* pan/happi/yield_in_term_to_binary: Add testcase to stress extra_root term_to_binary: Remove debug code and set production trap levels Teach erl_gc:offset_rootset about extra_root Teach external.c to handle reallocs before compression Make all steps ofterm_to_binary work in chunks and yield Make term_to_binary yield (trap). OTP-11163
2013-06-05Merge branch 'pan/r16b01/system_monitor_long_schedule/OTP-11067' into maintPatrik Nyblom
* pan/r16b01/system_monitor_long_schedule/OTP-11067: Minor spelling correction Add system_monitor of long_schedule
2013-06-05Make all steps ofterm_to_binary work in chunks and yieldPatrik Nyblom
Rewrite and extend of Happi's initial work Extra_root to process structure to enable GC of state - Changed the process structure to point to a separate struct, the struct also contains a destructor function to allow for proper cleanup. Rewrote encode_size_struct and enc_term to have internal versions with reduction counters which will result in interrupt for later restart when the counter reaches zero - removed the EWA_STACK from Happis version and directly save the ESTACK's and WSTACK's in the above mentioned struct (or array thereof) that are pointed out from the process structure. The destructor will take care of the deallocation in case of process death. Added ESTACK and WSTACK macros to save and restore stack and to change allocator, which makes the previously mentioned stack-save work. Rewrote enc_term to not store pointers on the stack, and use one WSTACK for commands etc and another ESTACK for Eterms - Slightly different than Happis version to make halfword code simpler. Rewrote encode_size_struct2 so that it does not store pointers on the stack, also switched to ESTACK instead of WSTACK, this also handles halfword correctly. Added interfaces for chunkwise compression, that are used from term_to_binary/2 when the compressed option is given.
2013-06-04Make term_to_binary yield (trap).happi
2013-06-04erts: Use carrier pool for migration of carriersRickard Green
2013-05-31Replace gc stat lock with sched spec dataLukas Larsson
2013-05-02Add system_monitor of long_schedulePatrik Nyblom
2013-02-11Make prim_file skip invalid filenames in unicode modePatrik Nyblom
The fix affects list_dir and read_link. Raw filenames are now never produced, just consumed even if +fnu or +fna is used on Linux etc. This also adds the options to get error return or error handler warning messages with +fn{u|a}{i|w|e} as an option to erl. This is still not documented and there needs to be other versions of read_dir and read_link to facilitate reading of all types of filenames and links. A check that we will not change to an invalid directory is also needed.
2013-01-25Update copyright yearsBjörn-Egil Dahlberg
2013-01-23Merge branch 'sverk/r16/utf8-atoms'Sverker Eriksson
* sverk/r16/utf8-atoms: erl_interface: Fix bug when transcoding atoms from and to UTF8 erl_interface: Changed erlang_char_encoding interface erts: Testcase doing unicode atom printout with ~w erl_interface: even more utf8 atom stuff erts: Fix bug in analyze_utf8 causing faulty latin1 detection Add UTF-8 node name support for epmd workaround... Fix merge conflict with hasse UTF-8 atom documentation test case erl_interface: utf8 atoms continued Add utf8 atom distribution test cases atom fixes for NIFs and atom_to_binary UTF-8 support for distribution Implement UTF-8 atom support for jinterface erl_interface: Enable decode of unicode atoms stdlib: Fix printing of unicode atoms erts: Change internal representation of atoms to utf8 erts: Refactor rename DFLAG(S)_INTERNAL_TAGS for conformity Conflicts: erts/emulator/beam/io.c OTP-10753
2013-01-21Text representation of a float formatted using given options.Serge Aleynikov
This BIF solves a problem of float_to_list/1 that doesn't allow specifying the number of digits after the decimal point when formatting floats. float_to_list(Float, Options) -> string() Float = float() Options = [Option] Option = {decimals, Decimals::0..249} | {scientific, Decimals::0..249} | compact Returns a string which corresponds to the text representation of a `Float` formatted using given options. When decimals option is specified the returned value will contain at most `Decimals` number of digits past the decimal point. When `compact` option is provided the trailing zeros at the end of the list are truncated (this option is only meaningful together with the `decimals` option). When `scientific` option is provided, the float will be formatted using scientific notation with `Decimals` digits of precision. If `Options` is `[]` the function behaves like `float_to_list/1`. When using `decimals` option and the number doesn't fit in the static internal buffer of 256 bytes the function throws `badarg`.
2013-01-16UTF-8 support for distributionRickard Green
2012-12-07Merge branch 'rickard/port-optimizations/OTP-10336' into ↵Rickard Green
rickard/r16/port-optimizations/OTP-10336 * rickard/port-optimizations/OTP-10336: Change annotate level for emacs-22 in cerl Update etp-commands Add documentation on communication in Erlang Add support for busy port message queue Add driver callback epilogue Implement true asynchronous signaling between processes and ports Add erl_drv_[send|output]_term Move busy port flag Use rwlock for driver list Optimize management of port tasks Improve configuration of process and port tables Remove R9 compatibility features Use ptab functionality also for ports Prepare for use of ptab functionality also for ports Atomic port state Generalize process table implementation Implement functionality for delaying thread progress from unmanaged threads Conflicts: erts/doc/src/erl_driver.xml erts/doc/src/erlang.xml erts/emulator/beam/beam_bif_load.c erts/emulator/beam/beam_bp.c erts/emulator/beam/beam_emu.c erts/emulator/beam/bif.c erts/emulator/beam/copy.c erts/emulator/beam/erl_alloc.c erts/emulator/beam/erl_alloc.types erts/emulator/beam/erl_bif_info.c erts/emulator/beam/erl_bif_port.c erts/emulator/beam/erl_bif_trace.c erts/emulator/beam/erl_init.c erts/emulator/beam/erl_message.c erts/emulator/beam/erl_port_task.c erts/emulator/beam/erl_process.c erts/emulator/beam/erl_process.h erts/emulator/beam/erl_process_lock.c erts/emulator/beam/erl_trace.c erts/emulator/beam/export.h erts/emulator/beam/global.h erts/emulator/beam/io.c erts/emulator/sys/unix/sys.c erts/emulator/sys/vxworks/sys.c erts/emulator/test/port_SUITE.erl erts/etc/unix/cerl.src erts/preloaded/ebin/erlang.beam erts/preloaded/ebin/prim_inet.beam erts/preloaded/src/prim_inet.erl lib/hipe/cerl/erl_bif_types.erl lib/kernel/doc/src/inet.xml lib/kernel/src/inet.erl
2012-12-07Implement true asynchronous signaling between processes and portsRickard Green
2012-12-03Use ptab functionality also for portsRickard Green
2012-12-03Generalize process table implementationRickard Green
2012-10-15erts, heart: Ensure erl_crash.dump is writtenBjörn-Egil Dahlberg
When a crash dump is about to be written and we have heartbeat enabled on a system. We need time to write it before heart explicitly kills the beam.
2012-05-10Remove stale code for hybrid heap and incremental GCBjörn Gustavsson
The hybrid heap emulator was last working in the non-SMP R11B run-time system. When the constant pools were introduced in R12B, the hybrid heap emulator was not updated to handle them. At this point, the harm from reduced readability of the code is greater than any potential usefulness of keeping the code.
2012-05-10Remove support for erlang:system_info(global_heaps_size)Björn Gustavsson
2012-04-17Extend erlang:port_info/1,2 to show the OS pid of a spawned processMatthias Lang
When spawning OS (unix) processes with erlang:open_port, store the resulting unix pid so that it can be queried later on using erlang:port_info/1,2.
2012-03-30Update copyright yearsBjörn-Egil Dahlberg
2012-03-22Add user tag spreading functionality to VM and use in filePatrik Nyblom
User tags in a dynamic trace enabled VM are spread throughout the system in the same way as seq_trace tokens. This is used by the file module and various other modules to get hold of the tag from the user process without changing the protocol.
2012-01-26Implement statistics(scheduler_wall_time)Rickard Green
2011-11-13Merge branch 'rickard/alloc-opt/OTP-7775'Rickard Green
* rickard/alloc-opt/OTP-7775: Optimize memory allocation Conflicts: erts/aclocal.m4 erts/emulator/hipe/hipe_bif_list.m4 erts/preloaded/ebin/erl_prim_loader.beam erts/preloaded/ebin/erlang.beam erts/preloaded/ebin/init.beam erts/preloaded/ebin/otp_ring0.beam erts/preloaded/ebin/prim_file.beam erts/preloaded/ebin/prim_inet.beam erts/preloaded/ebin/prim_zip.beam erts/preloaded/ebin/zlib.beam
2011-11-13Optimize memory allocationRickard Green
A number of memory allocation optimizations have been implemented. Most optimizations reduce contention caused by synchronization between threads during allocation and deallocation of memory. Most notably: * Synchronization of memory management in scheduler specific allocator instances has been rewritten to use lock-free synchronization. * Synchronization of memory management in scheduler specific pre-allocators has been rewritten to use lock-free synchronization. * The 'mseg_alloc' memory segment allocator now use scheduler specific instances instead of one instance. Apart from reducing contention this also ensures that memory allocators always create memory segments on the local NUMA node on a NUMA system.
2011-08-18Implement process_info(Pid, current_{location,stacktrace})Björn Gustavsson
2011-05-20Update copyright yearsBjörn-Egil Dahlberg
2011-05-13Fix build with hipe on amd64Rickard Green
2010-09-02Add erlang:system_info(build_type)Rickard Green
Added erlang:system_info(build_type) which makes it easier to chose drivers, NIF libraries, etc based on build type of the runtime system.
2010-08-10Rewrite ethread libraryRickard Green
Large parts of the ethread library have been rewritten. The ethread library is an Erlang runtime system internal, portable thread library used by the runtime system itself. 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 `{read_concurrency, true}' option upon table creation. See the documentation of `ets:new/2' for more information. The ethread library can now also use the libatomic_ops library for atomic memory accesses. This makes it possible for the Erlang runtime system to utilize optimized atomic operations on more platforms than before. Use the `--with-libatomic_ops=PATH' configure command line argument when specifying where the libatomic_ops installation is located. The libatomic_ops library can be downloaded from: http://www.hpl.hp.com/research/linux/atomic_ops/ The changed API of the ethread library has also caused modifications in the Erlang runtime system. Preparations for the to come "delayed deallocation" feature has also been done since it depends on the ethread library. Note: When building for x86, the ethread library will now use instructions that first appeared on the pentium 4 processor. If you want the runtime system to be compatible with older processors (back to 486) you need to pass the `--enable-ethread-pre-pentium4-compatibility' configure command line argument when configuring the system.