From 992831c7a516b5183c2af06260829d41aa45267c Mon Sep 17 00:00:00 2001 From: =?UTF-8?q?Lo=C3=AFc=20Hoguin?= Date: Thu, 9 Sep 2021 12:15:32 +0200 Subject: Ranch 2.1.0 --- .../en/ranch/2.1/guide/migrating_from_1.7.asciidoc | 163 +++++++++++++++++++++ 1 file changed, 163 insertions(+) create mode 100644 docs/en/ranch/2.1/guide/migrating_from_1.7.asciidoc (limited to 'docs/en/ranch/2.1/guide/migrating_from_1.7.asciidoc') diff --git a/docs/en/ranch/2.1/guide/migrating_from_1.7.asciidoc b/docs/en/ranch/2.1/guide/migrating_from_1.7.asciidoc new file mode 100644 index 00000000..e9b1c96e --- /dev/null +++ b/docs/en/ranch/2.1/guide/migrating_from_1.7.asciidoc @@ -0,0 +1,163 @@ +[appendix] +== Migrating from Ranch 1.7+ to Ranch 2.0 + +Ranch 2.0 adds support for multiple connection supervisors. + +Ranch 1.x had a bottleneck because it used only a single +connection supervisor. This was more evident when many +connections were dropped at once as the supervisor couldn't +keep up and failed to accept new connections while cleaning +up the old ones. Ranch 2.0 behaves much better in this scenario +by default. Multiple connection supervisors also helps with +concurrently accepting new connections. + +Ranch 2.0 also adds experimental support for opening more +than one listening socket on a single port. + +Starting with Ranch 2.0 we are also providing a +https://github.com/juhlig/prometheus_ranch[Prometheus collector] +as a separate project as well as a +https://github.com/juhlig/prometheus_ranch/blob/master/dashboards/ranch-dashboard.json[Grafana dashboard]. + +Ranch 2.0 is compatible with Erlang/OTP 21.0 onward. Support +for Erlang/OTP 19 and 20 has been removed. + +=== Features added + +* Ranch now comes with a `ranch.appup` file necessary for + performing release upgrades. A test suite has been added + to confirm release upgrades work from one tag to the next. + Numerous fixes were made that will also improve error recovery. + Release upgrades will only be supported from Ranch 2.0 + onward. + +* The `num_conns_sups` option has been added. It allows + configuring the number of connection supervisors. It + now defaults to `num_accceptors`. The old behavior can + be obtained by setting this value to 1. + +* The `logger` option is no longer experimental. It now + defaults to `logger` instead of `error_logger`. + +* UNIX domain sockets are now supported. + +* The active N socket option is now supported. It requires + Erlang/OTP 21.3 or above for TLS, however. + +* Embedded listeners are now failing in a predictable + manner when `ranch_server` goes down. It is no longer + necessary to embed `ranch_sup` and the recommendation + is now to just start Ranch normally when using embedded + listeners. + +* Two steps handshake is now supported. This allows + obtaining TLS extensions and updating options before + resuming the handshake. The handshake can also be + canceled. + +=== Experimental features added + +* The experimental `num_listen_sockets` option has been + added. It allows opening more than one listening socket + per listener. It can only be used alongside the Linux + `SO_REUSEPORT` socket option or equivalent. It allows + working around a bottleneck in the kernel and maximizes + resource usage, leading to increased rates for accepting + new connections. + +=== Features removed + +* The `socket` option was removed. A more viable solution + is to define a custom transport module that returns a fresh + socket when `Transport:listen/1` is called. + +=== Changed behaviors + +* The callback function `Transport:listen/1` and its + implementations in `ranch_tcp` and `ranch_ssl` have changed + to accept a map of transport options instead of only + socket options. + +* The callback function `Transport:messages/0` return value + now includes the tag used for passive messages. + +* The `Socket` argument was removed from `Protocol:start_link/3`. + The socket must now be obtained by calling `ranch:handshake/1,2`. + +=== Added functions + +* The functions `ranch:handshake_continue/1,2` and + `ranch:handshake_cancel/1` can be used to perform + a two steps handshake. These functions may not be + supported by all transports. + +=== Changed functions + +* The `NumAcceptors` argument was removed from `ranch:start_listener/5` + and `ranch:child_spec/5` and moved to the transport options. + +* Ranch options can no longer be passed along with socket options + as a proplist. The only forms allowed are now the `ranch:opts()` + map or only socket options as-is. Individual transport options + are now validated as well. The `ranch:opts()` map must + be used when socket options also use a map. This applies to the + `ranch:start_listener/5`, `ranch:child_spec/5` and + `ranch:set_transport_options/2` functions. + +* The function `ranch:info/1,2` now returns a map containing + each listener's information rather than a list of key/values. + The key `num_acceptors` was removed as it can be found in the + transport options. + +* The function `ranch:set_transport_options/2` no longer requires + the listener to be suspended. Which options apply immediately, + on suspend/resume or on restart has been documented. Some work + has also been done to make these option changes more predictable. + +=== Removed functions + +* The function `ranch:accept_ack/1` has been removed in favor + of `ranch:handshake/1,2`. + +=== Bugs fixed + +* Calling `ranch:remove_connection/1` will now resume a sleeping + acceptor process when applicable. + +* Repeatedly calling `ranch:remove_connection/1` from a connection + process would crash the respective connection supervisor. This has + now been fixed. + +* When a connection process was failing to start, the socket was + not closed and this lead to leaking sockets. This is now corrected. + +=== Other changes + +* Connection draining has now been documented in the guide + following user feedback and discussions. + +* Ranch is now tested against https://concuerror.com/[Concuerror], + a model checking tool for debugging, testing and verifying + concurrent Erlang programs. Two tests have been added in this + release and more will follow in the future. + +* Ranch is now tested against `stampede`, a chaos monkey style + testing tool. Currently includes three scenarios: normal + TCP and TLS listeners and embedded TCP listener. This new + test suite helped uncover a misplaced `monitor/2` call + added during the development of Ranch 2.0 (we were using a + similar tool, `havoc`, at the time of finding that issue). + +* The supervisor for acceptors and the parent supervisor for + connection supervisors now have an adaptive restart + intensity limit set to `1 + ceil(math:log2(NumChildren))` + to allow room for errors when they have many children. + +* Ranch now uses stricter compiler options. Missing function + specs were added to internal modules. + +* Ranch now calls `ssl:handshake/1,2,3` instead of + `ssl:ssl_accept/1,2`. + +* The `ranch_ssl:ssl_opt()` type has been updated to conform + with Erlang/OTP 23.0. -- cgit v1.2.3