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--- HIGHLIGHTS ------------------------------------------------------
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OTP-15991 Application(s): erts, stdlib
Related Id(s): PR-5208
Users can now configure ETS tables with the
{write_concurrency, auto} option. This option forces
tables to automatically change the number of locks that
are used at run-time depending on how much concurrency
is detected. The {decentralized_counters, true} option
is enabled by default when {write_concurrency, auto} is
active.
Benchmark results comparing this option with the other
ETS optimization options are available here:
https://erlang.org/bench/ets_bench_result_lock_config.html
OTP-16702 Application(s): compiler, erts
To enable more optimizations, BEAM files compiled with
OTP 21 and earlier cannot be loaded in OTP 25.
OTP-16982 Application(s): erts
Related Id(s): PR-5020
The signal queue of a process with
message_queue_data=off_heap* has been optimized to
allow parallel reception of signals from multiple
processes.
This is possible to do as Erlang only guarantees that
signals (i.e., message signals and non-message signals)
sent from a single process to another process are
ordered in send order. However, there are no ordering
guarantees for signals sent from different processes to
a particular process. Therefore, several processes can
send signals in parallel to a specific process without
synchronizing with each other. However, such signal
sending was previously always serialized as the senders
had to acquire the lock for the outer signal queue of
the receiving process. This parallel signal sending
optimization yields much better scalability for signal
sending than what was previously possible, see
https://erlang.org/bench/sigq_bench_result.html for
benchmark results.
* Information about how to enable the
message_queue_data=off_heap setting can be found in the
documentation of the function erlang:process_flag/2.
OTP-17119 Application(s): erts
Related Id(s): PR-4869
The JIT now works for 64-bit ARM processors.
OTP-17151 Application(s): compiler, erts
Related Id(s): ERIERL-590, PR-5479
Added support for the compile attribute -nifs() to
empower compiler and loader with information about
which functions may be overridden as NIFs by
erlang:load_nif/2. It is recommended to use this
attribute in all modules that load NIF libraries.
OTP-17351 Application(s): stdlib
Related Id(s): GH-4673, PR-4952
The format_status/2 callback for gen_server, gen_statem
and gen_event has been deprecated in favor of the new
format_status/1 callback.
The new callback adds the possibility to limit and
change many more things than the just the state, such
as the last received message, the reason for
terminating and more events specific to each type of
behavior. See the respective modules documentation for
more details.
OTP-17481 Application(s): stdlib
Related Id(s): PR-4811
The timer module has been modernized and made more
efficient, which makes the timer server less
susceptible to being overloaded. The timer:sleep/1
function now accepts an arbitrarily large integer.
OTP-17504 Application(s): compiler, erts
Related Id(s): GH-4971, PR-5281, PR-5752
When binary construction using the binary syntax fails,
the error message printed in the shell and by
erl_error:format_exception/3,4 will contain more
detailed information about what went wrong.
OTP-17684 Application(s): compiler, erts
Related Id(s): PR-5316, PR-5664
The Erlang compiler now includes type information in
BEAM files, and the JIT can now use that type
information to do optimizations such as eliminating or
simplifying type tests.
OTP-17705 Application(s): compiler
Related Id(s): PR-5411
The maybe ... end construction proposed in EEP-49 has
been implemented. It can simplify complex code where
otherwise deeply nested cases would have to be used.
To enable maybe, give the option -enable-feature
maybe_expr to erlc or add -feature(enable, maybe_expr).
inside the module.
OTP-17710 Application(s): otp
Related Id(s): PR-5597
A new DEVELOPMENT how-to guide has been added that
describes how to build and test Erlang/OTP when fixing
bugs or developing new functionality.
The makefile system has been extended to make it easier
to run tests at different granulates directly from the
command line. This new functionality is described in
the development how-to.
Using the extended makefile system, testing has been
added to the Github actions run for each opened PR so
that more bugs are caught earlier when bug fixes and
new features are proposed.
OTP-17720 Application(s): common_test, kernel, stdlib
Related Id(s): PR-5162
The new module peer supersedes the slave module. The
slave module is now deprecated and will be removed in
OTP 27.
peer contains an extended and more robust API for
starting erlang nodes.
OTP-17784 Application(s): kernel, stdlib
Related Id(s): PR-5792
In order to make it easier for the user to manage
multiple outstanding asynchronous call requests, new
functionality utilizing request identifier collections
have been introduced in erpc, gen_server, gen_statem,
and gen_event.
OTP-17841 Application(s): compiler, erts
Related Id(s): PR-5694
When a record matching or record update fails, a
{badrecord,ExpectedRecordTag} exception used to be
raised. In this release, the exception has been changed
to {badrecord,ActualValue}, where ActualValue is the
actual that was found instead of the expected record.
OTP-17911 Application(s): kernel
Related Id(s): OTP-17843, PR-5611, PR-5687
*** POTENTIAL INCOMPATIBILITY ***
As of OTP 25, global will by default prevent
overlapping partitions due to network issues by
actively disconnecting from nodes that reports that
they have lost connections to other nodes. This will
cause fully connected partitions to form instead of
leaving the network in a state with overlapping
partitions.
Prevention of overlapping partitions can be disabled
using the prevent_overlapping_partitions kernel(6)
parameter, making global behave like it used to do.
This is, however, problematic for all applications
expecting a fully connected network to be provided,
such as for example mnesia, but also for global itself.
A network of overlapping partitions might cause the
internal state of global to become inconsistent. Such
an inconsistency can remain even after such partitions
have been brought together to form a fully connected
network again. The effect on other applications that
expects that a fully connected network is maintained
may vary, but they might misbehave in very subtle hard
to detect ways during such a partitioning. Since you
might get hard to detect issues without this fix, you
are strongly advised not to disable this fix. Also note
that this fix has to be enabled on all nodes in the
network in order to work properly.
OTP-17953 Application(s): stdlib
Related Id(s): PR-5621
Added filelib:ensure_path/1 that ensures that all
directories for the given path exists (unlike
filelib:ensure_dir/1, which will not create the last
segment of the path).
OTP-17969 Application(s): stdlib
Related Id(s): PR-5588
The functions groups_from_list/2 and groups_from_list/3
have been added to the maps module.
OTP-17977 Application(s): stdlib
Related Id(s): GH-5606, PR-5766
The functions uniq/1 and uniq/2 for removing duplicates
have been added to the lists module.
OTP-17988 Application(s): compiler, kernel, stdlib, syntax_tools
Added support for selectable features as described in
EEP-60. Features can be enabled/disabled during
compilation with options (ordinary and +term) to erlc
as well as with directives in the file. Similar options
can be used to erl for enabling/disabling features
allowed at runtime. The new maybe expression (EEP-49)
is fully supported as the feature maybe_expr.
OTP-18039 Application(s): compiler
Change format of feature options and directives for
better consistency. Options to erlc and the
-compile(..) directive now has the format {feature,
feature-name, enable | disable}. The -feature(..) now
has the format -feature(feature-name, enable |
disable).
---------------------------------------------------------------------
--- POTENTIAL INCOMPATIBILITIES -------------------------------------
---------------------------------------------------------------------
OTP-17544 Application(s): stdlib
Related Id(s): PR-5008
Fix gen_server:call with the first argument as self()
to throw an error instead of failing with a timeout.
The same fix has also been done for gen_statem:call/3,
gen_event:sync_notify/2 and any other functionality
relying on the internal gen:call/3 function.
A similar fix was also done when using io:format/2 and
the current group_leader was set to the current
process.
OTP-17569 Application(s): erts
Related Id(s): PR-4793
The growth rate of writable binaries has been adjusted
to only increase by 20% after 16MB in size. Before this
change the size would always double.
This change may degrade write performance of large
binaries.
OTP-17627 Application(s): inets, stdlib
Adjust uri_string:normalize behavior for URIs with
undefined port (URI string with a port colon but no
port value or URI map with port => undefined).
Remove redundant normalization from http_request
module.
Before this change, normalize would not remove port
subcomponent in such cases and could for example return
"http://localhost:" URI.
OTP-17644 Application(s): dialyzer
Related Id(s): PR-5223
Fixed a bug that could cause the type analyzer to enter
an infinite loop.
OTP-17681 Application(s): kernel
Related Id(s): PR-5307
The most, or at least the most used, rpc operations now
require erpc support in order to communicate with other
Erlang nodes. erpc was introduced in OTP 23. That is,
rpc operations against Erlang nodes of releases prior
to OTP 23 will fail.
OTP-17683 Application(s): erts
Related Id(s): PR-5306
Distributed spawn operations now require distributed
spawn_request() support. Distributed spawn_request()
was introduced in OTP 23. That is, distributed spawn
operations against Erlang nodes of releases prior to
OTP 23 will fail.
OTP-17821 Application(s): dialyzer
Related Id(s): GH-5016, OTP-17554, PR-5408
The default location of the plt has been changed from
$HOME to filename:basedir(user_cache,"erlang").
OTP-17866 Application(s): inets
This change removes deprecated functions:
http_uri:parse/1, http_uri:parse/2 and
http_uri:scheme_defaults/0.
This change delays until OTP-26 removal of deprecated
functions: http_uri:encode/1 and http_uri:decode/1.
This change marks httpd_util:decode_hex/1 and
httpd_util:encode_hex/1 as deprecated.
OTP-17889 Application(s): inets
Fixed typo in Reason term returned from
httpc_handler:handle_http_body.
After this change, could_not_establish_ssl_tunnel atom
is returned within Reason term.
OTP-17894 Application(s): syntax_tools
Related Id(s): PR-5509
The erl_syntax_lib:analyze_attribute/1 function would
return {Name, {Name, Value}} instead of {Name, Value}
(which is the documented return value).
OTP-17911 Application(s): kernel
Related Id(s): OTP-17843, PR-5611, PR-5687
*** HIGHLIGHT ***
As of OTP 25, global will by default prevent
overlapping partitions due to network issues by
actively disconnecting from nodes that reports that
they have lost connections to other nodes. This will
cause fully connected partitions to form instead of
leaving the network in a state with overlapping
partitions.
Prevention of overlapping partitions can be disabled
using the prevent_overlapping_partitions kernel(6)
parameter, making global behave like it used to do.
This is, however, problematic for all applications
expecting a fully connected network to be provided,
such as for example mnesia, but also for global itself.
A network of overlapping partitions might cause the
internal state of global to become inconsistent. Such
an inconsistency can remain even after such partitions
have been brought together to form a fully connected
network again. The effect on other applications that
expects that a fully connected network is maintained
may vary, but they might misbehave in very subtle hard
to detect ways during such a partitioning. Since you
might get hard to detect issues without this fix, you
are strongly advised not to disable this fix. Also note
that this fix has to be enabled on all nodes in the
network in order to work properly.
OTP-17920 Application(s): ssh
The representation of Edward curves (ed25519 and ed448)
inside ssh had a temporary representation (ed_pri and
ed_pub).
That is now changed to the public_key form. See the
manual for more information.
OTP-17921 Application(s): public_key
The deprecated public_key functions ssh_decode/2,
ssh_encode/2, ssh_hostkey_fingerprint/1 and
ssh_hostkey_fingerprint/2 are removed.
They are replaced by ssh_file:decode/2,
ssh_file:encode/2, ssh:hostkey_fingerprint/1 and
ssh:hostkey_fingerprint/2 respectively.
Note that the decode/2 and encode/2 are not exact
replacement functions, some minor changes may be
needed. Se the manual for more information.
OTP-17925 Application(s): stdlib
Related Id(s): PR-5631
The non-local function handler for the erl_eval can now
be called with either two or three arguments. When
called with three arguments, the first argument is the
annotation for the node in the abstract format.
All errors during evaluation will now be passed through
erlang:raise/3. If the restricted shell is active and
it does not let erlang:raise/3 through, evaluation
errors will be printed in less clear way. See the
documentation for restricted shell in shell.
OTP-17950 Application(s): wx
Added aux1Down and aux2Down fields to the wxMouseState
record. Since one record have been changed a
recompilation of user code might be required.
OTP-17965 Application(s): crypto
The infomation in error messages are increased.
Previously the error was signaled with en error class
exception badarg, notsup or error, and also in some
more ways like an other exception or a return value in
a non-standardized format.
Now it is an error-class exception
{notsup|badarg|error, InfoFromCfile,
Description::string()}.
The InfoFromCfile is a term with name and line number
of the C-file where the error was found. This is
primarily intended for a crypto maitntainer or an
advanced user to find the cause of complicated errors -
maybe in crypto itself. The contents of that term might
be changed in the future.
The Description is a clear text string that describes
the error. In case of badarg and notsup the intention
is that it should help the user to find the cause ("Bad
key size" as an example). Specially for some error that
are unlikely, the string may not be possible to
understand without deep knowledge of the underlying
cryptolib. Such messages are intended for a crypto
maintainer.
The first element on call stack (the S in try ... catch
error:E:S .... end) gives more information like the
actual argument list in the call of crypto and the
argument number (if possible) in the call to the NIF
inside crypto.
The functions in crypto affected by this change are:
sign/4, sign/5, verify/5, verify/6,
generate_key/2, generate_key/3, compute_key/4,
hash/2, hash/4, hash_init/1, hash_update/4,
hash_final/1,
mac/3,4, mac_init/3, mac_update/2, mac_final/2,
pbkdf2_hmac/5,
public_encrypt/4, private_decrypt/4, private_encrypt/4,
public_decrypt/4
This schema was introduced earlier in:
crypto_init/3, crypto_init/4, crypto_update/2,
crypto_final/1, crypto_get_data/1,
crypto_one_time/4, crypto_one_time/5,
crypto_one_time_aead/6, crypto_one_time_aead/7
OTP-17991 Application(s): stdlib
The function filename:safe_relative_path/1, which has
been deprecated since OTP 25, has been removed. Use
filelib:safe_relative_path/2 instead.
OTP-18009 Application(s): stdlib
Related Id(s): PR-5785
Fixed string:next_grapheme/1 to return an empty binary
in the tail for binary input for the last grapheme
cluster.
erlang/otp
OTP-25.0-rc3
OTP 25.0-rc3
on GitHub
2 years ago