HAProxy - Load balancer
Find a file
Willy Tarreau 18ed789ae2 BUG/MEDIUM: server: don't kill all idle conns when there are not enough
In srv_cleanup_idle_connections(), we compute how many idle connections
are in excess compared to the average need. But we may actually be missing
some, for example if a certain number were recently closed and the average
of used connections didn't change much since previous period. In this
case exceed_conn can become negative. There was no special case for this
in the code, and calculating the per-thread share of connections to kill
based on this value resulted in special value -1 to be passed to
srv_migrate_conns_to_remove(), which for this function means "kill all of
them", as used in srv_cleanup_connections() for example.

This causes large variations of idle connections counts on servers and
CPU spikes at the moment the cleanup task passes. These were quite more
visible with SSL as it costs CPU to close and re-establish these
connections, and it also takes time, reducing the reuse ratio, hence
increasing the amount of connections during reconnection.

In this patch we simply skip the killing loop when this condition is met.

No backport is needed, this is purely 2.2.
2020-07-02 19:05:30 +02:00
.github CI: extend spellchecker whitelist 2020-06-26 11:26:52 +02:00
contrib CONTRIB: debug: add missing flags SI_FL_L7_RETRY & SI_FL_D_L7_RETRY 2020-06-28 16:05:39 +02:00
doc MINOR: log-format: allow to preserve spacing in log format strings 2020-07-02 10:11:44 +02:00
examples CLEANUP: assorted typo fixes in the code and comments 2020-06-26 11:27:28 +02:00
include MINOR: log: add time second fraction field to rfc5424 log timestamp. 2020-07-02 17:56:06 +02:00
reg-tests BUG/MINOR: http-rules: Fix ACLs parsing for http deny rules 2020-06-30 09:32:03 +02:00
scripts CI: travis-ci: switch BoringSSL builds to ninja 2020-06-26 11:26:26 +02:00
src BUG/MEDIUM: server: don't kill all idle conns when there are not enough 2020-07-02 19:05:30 +02:00
tests REORG: include: split mini-clist into haproxy/list and list-t.h 2020-06-11 10:18:56 +02:00
.cirrus.yml CI: cirrus-ci: skip reg-tests/connection/proxy_protocol_send_unique_id_alpn.vtc on CentOS 6 2020-05-28 16:51:36 +02:00
.gitignore DOC: create a BRANCHES file to explain the life cycle 2019-06-15 22:00:14 +02:00
.travis.yml CI: travis-ci: switch BoringSSL builds to ninja 2020-06-26 11:26:26 +02:00
BRANCHES DOC: assorted typo fixes in the documentation 2020-03-09 14:45:58 +01:00
CHANGELOG [RELEASE] Released version 2.2-dev11 2020-06-26 22:01:04 +02:00
CONTRIBUTING DOC: assorted typo fixes in the documentation and Makefile 2020-03-06 10:49:55 +01:00
INSTALL BUILD: Makefile: add linux-musl to TARGET 2020-04-16 15:17:13 +02:00
LICENSE LICENSE: add licence exception for OpenSSL 2012-09-07 13:52:26 +02:00
MAINTAINERS REORG: include: split hathreads into haproxy/thread.h and haproxy/thread-t.h 2020-06-11 10:18:56 +02:00
Makefile REORG: buffer: rename buffer.c to dynbuf.c 2020-06-29 09:26:59 +02:00
README DOC: create a BRANCHES file to explain the life cycle 2019-06-15 22:00:14 +02:00
ROADMAP DOC: update the outdated ROADMAP file 2019-06-15 21:59:54 +02:00
SUBVERS BUILD: use format tags in VERDATE and SUBVERS files 2013-12-10 11:22:49 +01:00
VERDATE [RELEASE] Released version 2.2-dev11 2020-06-26 22:01:04 +02:00
VERSION [RELEASE] Released version 2.2-dev11 2020-06-26 22:01:04 +02:00

The HAProxy documentation has been split into a number of different files for
ease of use.

Please refer to the following files depending on what you're looking for :

  - INSTALL for instructions on how to build and install HAProxy
  - BRANCHES to understand the project's life cycle and what version to use
  - LICENSE for the project's license
  - CONTRIBUTING for the process to follow to submit contributions

The more detailed documentation is located into the doc/ directory :

  - doc/intro.txt for a quick introduction on HAProxy
  - doc/configuration.txt for the configuration's reference manual
  - doc/lua.txt for the Lua's reference manual
  - doc/SPOE.txt for how to use the SPOE engine
  - doc/network-namespaces.txt for how to use network namespaces under Linux
  - doc/management.txt for the management guide
  - doc/regression-testing.txt for how to use the regression testing suite
  - doc/peers.txt for the peers protocol reference
  - doc/coding-style.txt for how to adopt HAProxy's coding style
  - doc/internals for developer-specific documentation (not all up to date)