linux-kernel.vger.kernel.org archive mirror
 help / color / mirror / Atom feed
From: Rik van Riel <riel@surriel.com>
To: torvalds@linux-foundation.org
Cc: davidlohr.bueso@hp.com, linux-kernel@vger.kernel.org,
	akpm@linux-foundation.org, hhuang@redhat.com, jason.low2@hp.com,
	walken@google.com, lwoodman@redhat.com, chegu_vinod@hp.com
Subject: ipc,sem: sysv semaphore scalability
Date: Wed, 20 Mar 2013 15:55:30 -0400	[thread overview]
Message-ID: <1363809337-29718-1-git-send-email-riel@surriel.com> (raw)

Include lkml in the CC: this time... *sigh*
---8<---

This series makes the sysv semaphore code more scalable,
by reducing the time the semaphore lock is held, and making
the locking more scalable for semaphore arrays with multiple
semaphores.

The first four patches were written by Davidlohr Buesso, and
reduce the hold time of the semaphore lock.

The last three patches change the sysv semaphore code locking
to be more fine grained, providing a performance boost when
multiple semaphores in a semaphore array are being manipulated
simultaneously.

On a 24 CPU system, performance numbers with the semop-multi
test with N threads and N semaphores, look like this:

	vanilla		Davidlohr's	Davidlohr's +	Davidlohr's +
threads			patches		rwlock patches	v3 patches
10	610652		726325		1783589		2142206
20	341570		365699		1520453		1977878
30	288102		307037		1498167		2037995
40	290714		305955		1612665		2256484
50	288620		312890		1733453		2650292
60	289987		306043		1649360		2388008
70	291298		306347		1723167		2717486
80	290948		305662		1729545		2763582
90	290996		306680		1736021		2757524
100	292243		306700		1773700		3059159


             reply	other threads:[~2013-03-20 20:16 UTC|newest]

Thread overview: 129+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2013-03-20 19:55 Rik van Riel [this message]
2013-03-20 19:55 ` [PATCH 1/7] ipc: remove bogus lock comment for ipc_checkid Rik van Riel
2013-03-20 19:55 ` [PATCH 2/7] ipc: introduce obtaining a lockless ipc object Rik van Riel
2013-03-20 19:55 ` [PATCH 3/7] ipc: introduce lockless pre_down ipcctl Rik van Riel
2013-03-20 19:55 ` [PATCH 4/7] ipc,sem: do not hold ipc lock more than necessary Rik van Riel
2013-03-20 19:55 ` [PATCH 5/7] ipc,sem: open code and rename sem_lock Rik van Riel
2013-03-22  1:14   ` Davidlohr Bueso
2013-03-20 19:55 ` [PATCH 6/7] ipc,sem: have only one list in struct sem_queue Rik van Riel
2013-03-22  1:14   ` Davidlohr Bueso
2013-03-20 19:55 ` [PATCH 7/7] ipc,sem: fine grained locking for semtimedop Rik van Riel
2013-03-22  1:14   ` Davidlohr Bueso
2013-03-22 23:01   ` Michel Lespinasse
2013-03-22 23:38     ` Rik van Riel
2013-03-22 23:42     ` [PATCH 7/7 part3] fix for sem_lock Rik van Riel
2013-03-20 20:49 ` ipc,sem: sysv semaphore scalability Linus Torvalds
2013-03-20 20:56   ` Linus Torvalds
2013-03-20 20:57   ` Davidlohr Bueso
2013-03-21 21:10 ` Andrew Morton
2013-03-21 21:47   ` Peter Hurley
2013-03-21 21:50   ` Peter Hurley
2013-03-21 22:01     ` Andrew Morton
2013-03-22  3:38       ` Rik van Riel
2013-03-26 19:28   ` Dave Jones
2013-03-26 19:43     ` Andrew Morton
2013-03-29 16:17       ` Dave Jones
2013-03-29 18:00         ` Linus Torvalds
2013-03-29 18:04           ` Dave Jones
2013-03-29 18:10             ` Linus Torvalds
2013-03-29 18:43         ` Linus Torvalds
2013-03-29 19:06           ` Dave Jones
2013-03-29 19:13             ` Linus Torvalds
2013-03-29 19:26             ` Linus Torvalds
2013-03-29 19:36               ` Peter Hurley
2013-04-02 16:08                 ` Sasha Levin
2013-04-02 17:24                   ` Linus Torvalds
2013-04-02 17:52                   ` Linus Torvalds
2013-04-02 19:53                     ` Sasha Levin
2013-04-02 20:00                       ` Dave Jones
2013-03-29 19:33           ` Peter Hurley
2013-03-29 19:54             ` Linus Torvalds
2013-04-01  7:40           ` Stanislav Kinsbursky
2013-03-29 20:41         ` Linus Torvalds
2013-03-29 21:12           ` Linus Torvalds
2013-03-29 23:16             ` Linus Torvalds
2013-03-30  1:36               ` Emmanuel Benisty
2013-03-30  2:08                 ` Davidlohr Bueso
2013-03-30  3:02                   ` Emmanuel Benisty
2013-03-30  3:46                     ` Linus Torvalds
2013-03-30  4:33                       ` Emmanuel Benisty
2013-03-30  5:10                         ` Linus Torvalds
2013-03-30  5:57                           ` Emmanuel Benisty
2013-03-30 17:22                             ` Linus Torvalds
2013-03-31  2:38                               ` Emmanuel Benisty
2013-03-31  5:01                         ` Davidlohr Bueso
2013-03-31 13:45                           ` Rik van Riel
2013-03-31 17:10                             ` Linus Torvalds
2013-03-31 17:02                           ` Emmanuel Benisty
2013-03-30  2:09                 ` Linus Torvalds
2013-03-30  2:55                   ` Davidlohr Bueso
2013-03-29 19:01       ` Dave Jones
2013-05-03 15:03         ` Peter Hurley
2013-03-22  1:12 ` Davidlohr Bueso
2013-03-22  1:23   ` Linus Torvalds
2013-03-22  3:40     ` Rik van Riel
2013-03-22  7:30 ` Mike Galbraith
2013-03-22 11:04 ` Emmanuel Benisty
2013-03-22 15:37   ` Linus Torvalds
2013-03-23  3:19     ` Emmanuel Benisty
2013-03-23 19:45       ` Linus Torvalds
2013-03-24 13:46         ` Emmanuel Benisty
2013-03-24 17:10           ` Linus Torvalds
2013-03-25 13:47             ` Emmanuel Benisty
2013-03-25 14:00               ` Rik van Riel
2013-03-25 14:03                 ` Rik van Riel
2013-03-25 15:20                   ` Emmanuel Benisty
2013-03-25 15:53                     ` Rik van Riel
2013-03-25 17:09                       ` Emmanuel Benisty
2013-03-25 14:01               ` Rik van Riel
2013-03-25 14:21                 ` Emmanuel Benisty
2013-03-26 17:59               ` Davidlohr Bueso
2013-03-26 18:14                 ` Rik van Riel
2013-03-26 18:35                 ` Andrew Morton
2013-04-16 23:30                   ` Andrew Morton
2013-05-04 15:55       ` Jörn Engel
2013-05-04 18:12         ` Borislav Petkov
2013-05-06 14:47           ` Jörn Engel
2013-03-22 17:51 ` Davidlohr Bueso
2013-03-25 20:21 ` Sasha Levin
2013-03-25 20:38   ` [PATCH -mm -next] ipc,sem: fix lockdep false positive Rik van Riel
2013-03-25 21:42     ` Michel Lespinasse
2013-03-25 21:51       ` Michel Lespinasse
2013-03-25 21:56         ` Sasha Levin
2013-03-25 21:52       ` Sasha Levin
2013-03-26 13:19       ` Peter Zijlstra
2013-03-26 13:40         ` Michel Lespinasse
2013-03-26 14:27           ` Peter Zijlstra
2013-03-26 15:19             ` Rik van Riel
2013-03-27  8:40               ` Peter Zijlstra
2013-03-27  8:42               ` Peter Zijlstra
2013-03-27 11:22                 ` Michel Lespinasse
2013-03-27 12:02                   ` Peter Zijlstra
2013-03-27 20:00                 ` Rik van Riel
2013-03-28 20:23                 ` [PATCH v2 " Rik van Riel
2013-03-29  2:50                   ` Michel Lespinasse
2013-03-29  9:57                     ` Peter Zijlstra
2013-03-29 13:21                       ` Michel Lespinasse
2013-03-29 12:07                     ` Rik van Riel
2013-03-29 13:08                       ` Michel Lespinasse
2013-03-29 13:24                         ` Rik van Riel
2013-03-29 13:55                     ` [PATCH v3 " Rik van Riel
2013-03-29 13:59                       ` Michel Lespinasse
2013-03-26 14:25         ` [PATCH " Rik van Riel
2013-03-26 17:33 ` ipc,sem: sysv semaphore scalability Sasha Levin
2013-03-26 17:51   ` Davidlohr Bueso
2013-03-26 18:07     ` Sasha Levin
2013-03-26 18:17       ` Rik van Riel
2013-03-26 20:00       ` [PATCH -mm -next] ipc,sem: untangle RCU locking with find_alloc_undo Rik van Riel
2013-04-05  4:38         ` Mike Galbraith
2013-04-05 13:21           ` Rik van Riel
2013-04-05 16:26             ` Mike Galbraith
2013-04-16 12:37             ` Mike Galbraith
2013-03-26 17:55   ` ipc,sem: sysv semaphore scalability Paul E. McKenney
2013-03-28 15:32   ` [PATCH -mm -next] ipc,sem: untangle RCU locking with find_alloc_undo Rik van Riel
2013-03-28 21:05     ` Davidlohr Bueso
2013-03-29  1:00     ` Michel Lespinasse
2013-03-29  1:14       ` Sasha Levin
2013-03-30 13:35     ` Sasha Levin
2013-03-31  1:30       ` Rik van Riel
2013-03-31  4:09         ` Davidlohr Bueso

Reply instructions:

You may reply publicly to this message via plain-text email
using any one of the following methods:

* Save the following mbox file, import it into your mail client,
  and reply-to-all from there: mbox

  Avoid top-posting and favor interleaved quoting:
  https://en.wikipedia.org/wiki/Posting_style#Interleaved_style

* Reply using the --to, --cc, and --in-reply-to
  switches of git-send-email(1):

  git send-email \
    --in-reply-to=1363809337-29718-1-git-send-email-riel@surriel.com \
    --to=riel@surriel.com \
    --cc=akpm@linux-foundation.org \
    --cc=chegu_vinod@hp.com \
    --cc=davidlohr.bueso@hp.com \
    --cc=hhuang@redhat.com \
    --cc=jason.low2@hp.com \
    --cc=linux-kernel@vger.kernel.org \
    --cc=lwoodman@redhat.com \
    --cc=torvalds@linux-foundation.org \
    --cc=walken@google.com \
    /path/to/YOUR_REPLY

  https://kernel.org/pub/software/scm/git/docs/git-send-email.html

* If your mail client supports setting the In-Reply-To header
  via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line before the message body.
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox;
as well as URLs for NNTP newsgroup(s).