Age | Commit message (Collapse) | Author |
|
Persistent terms are useful for storing Erlang terms that are never
or infrequently updated. They have the following advantages:
* Constant time access. A persistent term is not copied when it is
looked up. The constant factor is lower than for ETS, and no locks
are taken when looking up a term.
* Persistent terms are not copied in garbage collections.
* There is only ever one copy of a persistent term (until it is
deleted). That makes them useful for storing configuration data
that needs to be easily accessible by all processes.
Persistent terms have the following drawbacks:
* Updates are expensive. The hash table holding the keys for the
persistent terms are updated whenever a persistent term is added,
updated or deleted.
* Updating or deleting a persistent term triggers a "global GC", which
will schedule a heap scan of all processes to search the heap of all
processes for the deleted term. If a process still holds a reference
to the deleted term, the process will be garbage collected and the
term copied to the heap of the process. This global GC can make the
system less responsive for some time.
Three BIFs (implemented in C in the emulator) is the entire
interface to the persistent term functionality:
* put(Key, Value) to store a persistent term.
* get(Key) to look up a persistent term.
* erase(Key) to delete a persistent term.
There are also two additional BIFs to obtain information about
persistent terms:
* info() to return a map with information about persistent terms.
* get() to return a list of a {Key,Value} tuples for all persistent
terms. (The values are not copied.)
|
|
Introudce erts_queue_release_literals() to queue a literal area to be
released.
|
|
In the implementation of the zero-copying term storage, we
want to preserve sharing, but not copy literals because the
modules holding the literals could be unloaded under our feet.
|
|
* Make connection_id part of the distribution handle as {ConnId, DistEntry}
in order for BIFs to verify correct connection.
* Make distribution handle opaque to net_kernel.
* Remove some unsafe lockless reads of DistEntry.flags
* Change state ERTS_DE_STATE_EXITING to be more of an internal state that
prevents erts from enqueue, encode or schedule new data to be sent. Otherwise
it should behave like ERTS_DE_STATE_CONNECTED.
|
|
This may be of interest in crash dumps and allows the upcoming
allocation tagging feature to track allocations on a per-NIF basis.
Note that this is only updated when user code calls a NIF; it's not
altered when the emulator calls NIFs during code upgrades or
tracing.
|
|
|
|
* rickard/process_info/OTP-14966:
New process_info() implementation using signals
|
|
|
|
* sverker/driver-taints/OTP-14960:
erts: Include foreign static linked drivers in taints
erts: Fix harmless bug in macro IS_DRIVER_VERSION_GE
erts: Remove our own NIF modules from "taints"
erts: Refactor erts_static_nif_get_nif_init
erts: Add dynamic loaded drivers to list of "taints"
|
|
That is, driver added with config option --enable-static-drivers.
|
|
Communication between Erlang processes has conceptually always been
performed through asynchronous signaling. The runtime system
implementation has however previously preformed most operation
synchronously. In a system with only one true thread of execution, this
is not problematic (often the opposite). In a system with multiple threads
of execution (as current runtime system implementation with SMP support)
it becomes problematic. This since it often involves locking of structures
when updating them which in turn cause resource contention. Utilizing
true asynchronous communication often avoids these resource contention
issues.
The case that triggered this change was contention on the link lock due
to frequent updates of the monitor trees during communication with a
frequently used server. The signal order delivery guarantees of the
language makes it hard to change the implementation of only some signals
to use true asynchronous signaling. Therefore the implementations
of (almost) all signals have been changed.
Currently the following signals have been implemented as true
asynchronous signals:
- Message signals
- Exit signals
- Monitor signals
- Demonitor signals
- Monitor triggered signals (DOWN, CHANGE, etc)
- Link signals
- Unlink signals
- Group leader signals
All of the above already defined as asynchronous signals in the
language. The implementation of messages signals was quite
asynchronous to begin with, but had quite strict delivery constraints
due to the ordering guarantees of signals between a pair of processes.
The previously used message queue partitioned into two halves has been
replaced by a more general signal queue partitioned into three parts
that service all kinds of signals. More details regarding the signal
queue can be found in comments in the erl_proc_sig_queue.h file.
The monitor and link implementations have also been completely replaced
in order to fit the new asynchronous signaling implementation as good
as possible. More details regarding the new monitor and link
implementations can be found in the erl_monitor_link.h file.
|
|
Dynamic NIF libs and those added with config option
--enable-static-nifs are considered as taints.
|
|
to return pointer to ErtsStaticNifEntry.
|
|
|
|
|
|
|
|
|
|
|
|
|
|
The reduction cost of sending messages is now constant and will no
longer scale according to the length of the receiving process'
message queue.
|
|
into utility functions.
|
|
putenv(3) and friends aren't thread-safe regardless of how you slice
it; a global lock around all environment operations (like before)
keeps things safe as far as our own operations go, but we have
absolutely no control over what libc or a library dragged in by a
driver/NIF does -- they're free to call getenv(3) or putenv(3)
without honoring our lock.
This commit solves this by setting up an "emulated" environment which
can't be touched without going through our interfaces. Third-party
libraries can still shoot themselves in the foot but benign uses of
os:putenv/2 will no longer risk crashing the emulator.
|
|
* maint:
Use base64 encoding in crash dumps
Correct parsing of sub binaries
Generalize passing of options for decoding
|
|
This will reduce the size of crash dumps, especially if
there are large binaries.
|
|
* maint:
Bump version of crash dumps to 0.4
Verify that binaries of different sizes are dumped correctly
Don't dump literal areas that are not referenced at all
Dump literals separately to avoid incomplete heap data
Implement dumping of maps in crash dumps
Buffer writing of crash dumps
Conflicts:
erts/emulator/beam/erl_alloc.types
|
|
|
|
* maint:
Revert "Merge branch 'rickard/null-char-filenames/ERL-370/OTP-14543' into maint"
|
|
This reverts commit 0717a2194e863f3a78595184ccc5637697f03353, reversing
changes made to 71a40658a0cef8b3e25df3a8e48a72d0563a89bf.
|
|
* maint:
Don't allow null in filenames
|
|
|
|
|
|
|
|
|
|
We don't need to pass x(0), x(1), and x(2) because they
can already be found in the register array.
|
|
* maint:
Unicode support for erlang:display_string/1
|
|
* rickard/unicode-display_string/OTP-14545:
Unicode support for erlang:display_string/1
|
|
|
|
|
|
* sverker/halt-unicode-slogan/OTP-14553:
erts: Allow any unicode string as crash dump slogan
erts: Generate crash_dump slogan string as UTF8
erts: Refactor erts_unicode_list_to_buf
|
|
|
|
|
|
This refactor was done using the unifdef tool like this:
for file in $(find erts/ -name *.[ch]); do unifdef -t -f defile -o $file $file; done
where defile contained:
#define ERTS_SMP 1
#define USE_THREADS 1
#define DDLL_SMP 1
#define ERTS_HAVE_SMP_EMU 1
#define SMP 1
#define ERL_BITS_REENTRANT 1
#define ERTS_USE_ASYNC_READY_Q 1
#define FDBLOCK 1
#undef ERTS_POLL_NEED_ASYNC_INTERRUPT_SUPPORT
#define ERTS_POLL_ASYNC_INTERRUPT_SUPPORT 0
#define ERTS_POLL_USE_WAKEUP_PIPE 1
#define ERTS_POLL_USE_UPDATE_REQUESTS_QUEUE 1
#undef ERTS_HAVE_PLAIN_EMU
#undef ERTS_SIGNAL_STATE
|
|
The implementation is still hidden behind ERTS_ENABLE_LOCK_COUNT, and
all categories are still enabled by default, but the actual counting can be
toggled at will.
OTP-13170
|
|
to get bytes written when truncated.
|
|
erts: Remove old unused functions
|
|
The functions have been found using: https://github.com/caolanm/callcatcher
|
|
|
|
* sverker/refactor:
erts: Introduce struct binary_internals
erts: Introduce erts_bin_release
erts: Init refc=1 in erts_bin_drv_alloc*
erts: Init refc=1 in erts_bin_nrml_alloc
erts: Remove deliberate leak of hipe fun entries
erts: Remove hipe_bifs:remove_refs_from/1
Refactor hipe specific code to use ErtsCodeInfo
erts: Refactor ErtsCodeInfo.native
|
|
to replace macro ERTS_INTERNAL_BINARY_FIELDS
as header in Binary and friends.
|
|
|