NEWS

Erlang OTP 21.0 is released
Written by Henrik, 20 Jun 2018

OTP 21

Erlang/OTP 21 is a new major release with new features, improvements as well as incompatibilities.

Potential Incompatibilities

  • All Corba applications are now moved from the OTP repository
  • A new Corba repository will be created https://github.com/erlang
  • New applications ftp and tftp, moved from inets
  • ssl no longer supports 3_DES cipher suites or RSA-key exchange cipher suites by default
  • erlang:monitor on a primitive node (erl_interface, jinterface, etc) will no longer fail with badarg exception. Instead a monitor will be created, but it will only supervise the connection to the node.

 Highlights

 Erts:

  • Enhanced IO scalability
  • Support for usage of distribution controller processes for alternative transports, routing etc
  • compact instructions on 64bit systems for code below 4GB 20% less memory for loaded code
  • Rewrite of the efile-driver with NIFs and "Dirty schedulers" resulting in faster file operations
  • non-smp VM removed
  • link and monitor optimized for scalability
  • os:getenv/putenv now work on thread-safe emulation. No longer in sync with libc getenv(3). Manual synchronization will be needed.

Compiler:

  • Misc compiler optimizations including contributions from the Elixir team resulting in 10% improvements in benchmarks
  • "Tuple calls" have been removed from the run-time system.
  • Code such as f({ok, Val}) -> {ok, Val} is now automatically rewritten to f({ok, Val} = Tuple) -> Tuple. this reduces code size, execution time, and removed GC pressure.
  • More information in stacktrace from a number of operators
  • erlang:get_stacktrace/0 deprecated to be replaced with try ... catch C:R:Stacktrace -> ...
  • Creation of small maps with literal keys optimized.
  • A new predifined macro `OTP_RELEASE` and preprocessor directives `-if` and `-elif`

Security:

  • DTLS is now supported in the SSL application
  • Enhanced support for distribution over TLS
  • "unsecure" ciphers removed from defaults in SSL and SSH.
  • A new option value defined to facilitate implementing exec servers. Old option kept for compatibility, but now gives errors on stderror.

Standard libraries:

  • New API for logging, logger
  • New uri_string module for parsing URIs according to "The standard"
  • New function lists:search(list,fun/1) -> {ok, Value} | false
  • Changed default behaviour of .erlang loading. escript, erlc, dialyzer and typer no longer load an .erlang at all.

For more details see
http://erlang.org/download/otp_src_21.0.readme

Pre built versions for Windows can be fetched here:
http://erlang.org/download/otp_win32_21.0.exe
http://erlang.org/download/otp_win64_21.0.exe

Online documentation can be browsed here:
http://erlang.org/documentation/doc-10.0/doc

The Erlang/OTP source can also be found at GitHub on the official Erlang repository, Here: OTP-21.0

 

Thank you for all your contributions!