HAProxy - Load balancer
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Willy Tarreau cabe945876 MINOR: ring: avoid writes to cells during copy
It has been found that performing a first pass consisting in copying
all messages, and a second one to notify about releases is more efficient
on AMD than updating all of them on the fly using a CAS, despite making
writers wait longer to be released.

Maybe it's related to the ability for the CPU to prefetch the contents
during a simple load while it wouldn't do it for an XCHG, it's unsure
at this point. This will also mater permit to use relaxed stores to
release threads.

On ARM the performance increased to 7.0M/s. If this patch is applied
before the dropping of the intermediary step, instead it drops to
3.9M/s. This shows the dependency between such changes that strive to
limit the number of writes on the fast path.

On x86_64, the EPYC at 3C6T saw a small drop from 4.57M to 4.45M, but
the 24C48T setup saw a nice 33% boost from 3.33M to 4.44M, i.e. we
get stable perf at 3 and 24 cores, despite having 8 CCX involved and
fighting with each other.

Other possibilities are:
  - use of HA_ATOMIC_XCHG() instead of FETCH_OR()
    => slightly faster (4.62/7.37 vs 4.58/7.34). Pb: requires to
       modify the readers to wait much longer since the tail value
       won't be valid in this case during updates, and it will have
       to wait by looping over it.
  - use other conditions to release a cell
    => to be tested
2024-03-25 17:34:19 +00:00
.github CI: temporarily adjust kernel entropy to work with ASAN/clang 2024-03-18 19:54:33 +01:00
addons CLEANUP: assorted typo fixes in the code and comments 2024-03-05 11:50:34 +01:00
admin BUILD: address a few remaining calloc(size, n) cases 2024-02-10 11:37:27 +01:00
dev MEDIUM: ring: use the topmost bit of the tail as a lock 2024-03-25 17:34:19 +00:00
doc MINOR: ring: make the number of queues configurable 2024-03-25 17:34:19 +00:00
examples CLEANUP: assorted typo fixes in the code and comments 2023-11-23 16:23:14 +01:00
include MINOR: ring: make the number of queues configurable 2024-03-25 17:34:19 +00:00
reg-tests OPTIM: http_ext: avoid useless copy in http_7239_extract_{ipv4,ipv6} 2024-03-25 16:24:15 +01:00
scripts CI: ssl: add yet another OpenSSL download fallback 2024-02-07 11:05:45 +01:00
src MINOR: ring: avoid writes to cells during copy 2024-03-25 17:34:19 +00:00
tests Revert "MAJOR: import: update mt_list to support exponential back-off" 2023-09-15 17:13:43 +02:00
.cirrus.yml CI: cirrus-ci: display gdb bt if any 2023-09-22 08:28:30 +02:00
.gitattributes MINOR: Configure the cpp userdiff driver for *.[ch] in .gitattributes 2021-02-22 18:17:57 +01:00
.gitignore CONTRIB: Add vi file extensions to .gitignore 2023-06-02 18:14:34 +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
BSDmakefile BUILD: makefile: commit the tiny FreeBSD makefile stub 2023-05-24 17:17:36 +02:00
CHANGELOG [RELEASE] Released version 3.0-dev5 2024-03-09 16:50:15 +01:00
CONTRIBUTING CLEANUP: assorted typo fixes in the code and comments 2021-08-16 12:37:59 +02:00
INSTALL DOC: install: recommend pcre2 2024-02-08 08:55:57 +01:00
LICENSE LICENSE: add licence exception for OpenSSL 2012-09-07 13:52:26 +02:00
MAINTAINERS MAJOR: spoe: Deprecate the SPOE filter 2024-03-15 11:29:39 +01:00
Makefile REORG: dns/ring: split the ring between the generic one and the DNS one 2024-03-25 17:34:19 +00:00
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 3.0-dev5 2024-03-09 16:50:15 +01:00
VERSION [RELEASE] Released version 3.0-dev5 2024-03-09 16:50:15 +01:00

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)