HAProxy - Load balancer
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Willy Tarreau f6a42c3a37 MINOR: freq_ctr: use the thread's local time whenever possible
Right now when dealing with freq_ctr updates, we're using the process-
wide monotinic time, and accessing it is expensive since every thread
needs to update it, so this adds some contention. However we don't need
it all the time, the thread's local time is most of the time strictly
equal to the global time, and may be off by one millisecond when the
global time is switched to the next one by another thread, and in this
case we don't want to use the local time because it would risk to cause
a rotation of the counter. But that's precisely the condition we're
already relying on for the slow path!

What this patch does is to add a check for the period against the
local time prior to anything else, and immediately return after
updating the counter if still within the period, otherwise fall back
to the existing code. Given that the function starts to inflate a bit,
it was split between s very short inline part that does the hot path,
and the slower fallback that's in a cold function. It was measured that
on a 24-CPU machine it was called ~0.003% of the time.

The resulting improvement sits between 2 and 3% at 500k req/s tracking
an http_req_rate counter.
2022-10-12 14:19:05 +02:00
.github CI: enable weekly "m32" builds on x86_64 2022-08-06 17:10:16 +02:00
addons CLEANUP: assorted typo fixes in the code and comments 2022-08-06 17:12:51 +02:00
admin BUILD: halog: fix some incorrect signs in printf formats for integers 2022-04-12 08:40:38 +02:00
dev MINOR: flags/mux-h1: decode H1C and H1S flags 2022-09-15 11:01:59 +02:00
doc DOC: configuration: missing 'if' in tcp-request content example 2022-10-12 09:22:05 +02:00
examples EXAMPLES: remove completely outdated acl-content-sw.cfg 2022-05-30 18:14:24 +02:00
include MINOR: freq_ctr: use the thread's local time whenever possible 2022-10-12 14:19:05 +02:00
reg-tests BUG/MINOR: checks: update pgsql regex on auth packet 2022-10-03 15:31:22 +02:00
scripts SCRIPTS: announce-release: update some URLs to https 2022-09-17 12:17:07 +02:00
src MINOR: freq_ctr: use the thread's local time whenever possible 2022-10-12 14:19:05 +02:00
tests TESTS: add a unit test for one_among_mask() 2022-06-21 20:29:57 +02:00
.cirrus.yml CI: cirrus-ci: bump FreeBSD image to 13-1 2022-09-09 13:30:17 +02:00
.gitattributes MINOR: Configure the cpp userdiff driver for *.[ch] in .gitattributes 2021-02-22 18:17:57 +01:00
.gitignore CLEANUP: exclude udp-perturb with .gitignore 2022-09-16 15:47:04 +02:00
.mailmap DOC: update Tim's address in .mailmap 2021-09-16 09:14:14 +02:00
.travis.yml CI: travis-ci: temporarily disable arm64 builds 2021-08-07 07:28:15 +02:00
BRANCHES DOC: fix some spelling issues over multiple files 2021-01-08 14:53:47 +01:00
CHANGELOG [RELEASE] Released version 2.7-dev7 2022-10-03 15:20:38 +02:00
CONTRIBUTING CLEANUP: assorted typo fixes in the code and comments 2021-08-16 12:37:59 +02:00
INSTALL BUILD: Makefile: Add Lua 5.4 autodetect 2022-07-04 17:28:48 +02:00
LICENSE LICENSE: add licence exception for OpenSSL 2012-09-07 13:52:26 +02:00
MAINTAINERS DOC: add maintainers for QUIC and HTTP/3 2022-05-30 17:34:51 +02:00
Makefile CLEANUP: quic: create a dedicated quic_conn module 2022-10-03 16:25:17 +02:00
README DOC: create a BRANCHES file to explain the life cycle 2019-06-15 22:00:14 +02:00
SUBVERS BUILD: use format tags in VERDATE and SUBVERS files 2013-12-10 11:22:49 +01:00
VERDATE [RELEASE] Released version 2.7-dev7 2022-10-03 15:20:38 +02:00
VERSION [RELEASE] Released version 2.7-dev7 2022-10-03 15:20:38 +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)