Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1751873Ab3CTUtz (ORCPT ); Wed, 20 Mar 2013 16:49:55 -0400 Received: from mail-vb0-f50.google.com ([209.85.212.50]:57414 "EHLO mail-vb0-f50.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1750850Ab3CTUty (ORCPT ); Wed, 20 Mar 2013 16:49:54 -0400 MIME-Version: 1.0 In-Reply-To: <1363809337-29718-1-git-send-email-riel@surriel.com> References: <1363809337-29718-1-git-send-email-riel@surriel.com> Date: Wed, 20 Mar 2013 13:49:53 -0700 X-Google-Sender-Auth: __aN6-R8QAjAEIoZB0ysx94etDg Message-ID: Subject: Re: ipc,sem: sysv semaphore scalability From: Linus Torvalds To: Rik van Riel Cc: Davidlohr Bueso , Linux Kernel Mailing List , Andrew Morton , hhuang@redhat.com, "Low, Jason" , Michel Lespinasse , Larry Woodman , "Vinod, Chegu" Content-Type: text/plain; charset=UTF-8 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1523 Lines: 34 On Wed, Mar 20, 2013 at 12:55 PM, Rik van Riel wrote: > > 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 series looks sane to me, and I like how each individual step is pretty small and makes sense. It *would* be lovely to see this run with the actual Swingbench numbers. The microbenchmark always looked much nicer. Do the additional multi-semaphore scalability patches on top of Davidlohr's patches help with the swingbench issue, or are we still totally swamped by the ipc lock there? Maybe there were already numbers for that, but the last swingbench numbers I can actually recall was from before the finer-grained locking.. And obviously, getting this tested so that there aren't any more missed wakeups etc would be lovely. I'm assuming the plan is that this all goes through Andrew? Do we have big semop users who could test it on real loads? Considering that I *suspect* the main users are things like Oracle etc, I'd assume that there's some RH lab or partner or similar that is interested in making sure this not only helps, but also that it doesn't break anything ;) Linus -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/