Erlang/OTP 20.1 is the first service release for the 20 major release. The service release contains mostly bug fixes and characteristics improvements but also some new features.
Some highlights for 20.1
- crypto, public_key: Extend crypto and public_key functions sign and verify with:
- support for RSASSA-PS padding for signatures and for saltlength setting
- X9.31 RSA padding.
- sha, sha224, sha256, sha384, and sha512 for dss signatures as mentioned in NIST SP 800-57 Part 1.
- ripemd160 to be used for rsa signatures.
- A new tuple in
crypto:supports/0reports supported MAC algorithms.
- Add service option
decode_formatto allow incoming messages to be decoded into maps instead of records.
- Decode performance has been improved.
- Add service/transport option avp_dictionaries to give better support for dictionaries only defining AVPs.
- erts: Upgraded the ERTS internal PCRE library from version 8.40 to version 8.41.
- erts, kernel, tools: Profiling with lock counting can now be fully toggled at runtime in
the lock counting emulator (-emu_type lcnt). Everything
is enabled by default to match the old behavior, but
specific categories can be toggled at will with minimal
runtime overhead when disabled. Refer to the
lcnt:clear will no longer block all
other threads in the runtime system. This makes it possible to run the lock counting
under heavier load.
- erts: The
zlibmodule has been refactored and all its operations will now yield appropriately, allowing them to be used freely in concurrent applications.
- erts, tools: Add
erlang:iolist_to_iovec/1, which converts an
erlang:iovec(), which is suitable for use with
- erts: Add new nif API functions for managing an I/O Queue.
The added functions are:
- Reading of crash dumps with many binaries is optimized.
- A progress bar is shown when the detail view for a process is opened.
- The cdv script now sets ERL_CRASH_DUMP_SECONDS=0 to avoid generating a new crash dump from the node running the Crashdump Viewer.
- observer: Add system statistics and limits to frontpage in observer.
- public_key, ssl**: Improved error propagation and reports
- ssh: A new option
modify_algorithmsis implemented. It enables specifying changes on the default algorithms list. See the reference manual and the SSH User’s Guide chapter “Configuring algorithms in SSH”.
- tools/xref: The predefined Xref analysis locals_not_used now understands
-on_load()attribute and does not report unused functions.
- tools/fprof: When sampling multiple processes and analyzing with totals set to true, the output now sums together all caller and callee entries which concerns the same function. Previous behaviour was to report each contributing entry separately.
You can find the README and the full listing of changes for this service release at
The source distribution and binary distributions for Windows can be downloaded from
Note: To unpack the TAR archive you need a GNU TAR compatible program.
For installation instructions please consult the README file that is part of the distribution.
The Erlang/OTP source can also be found at GitHub on the official Erlang repository, https://github.com/erlang/otp with tag OTP-20.1
The on-line documentation can be found at: https://www.erlang.org/doc/ You can also download the complete HTML documentation or the Unix manual files
Please report any new issues via Erlang/OTPs public issue tracker
We want to thank all of those who sent us patches, suggestions and bug reports!
The Erlang/OTP Team at Ericsson