From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1760875AbYEHJV2 (ORCPT ); Thu, 8 May 2008 05:21:28 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1755766AbYEHJVU (ORCPT ); Thu, 8 May 2008 05:21:20 -0400 Received: from mx3.mail.elte.hu ([157.181.1.138]:34241 "EHLO mx3.mail.elte.hu" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1755096AbYEHJVS (ORCPT ); Thu, 8 May 2008 05:21:18 -0400 Date: Thu, 8 May 2008 11:21:02 +0200 From: Ingo Molnar To: "Zhang, Yanmin" Cc: Linus Torvalds , Andi Kleen , Matthew Wilcox , LKML , Alexander Viro , Andrew Morton Subject: Re: AIM7 40% regression with 2.6.26-rc1 Message-ID: <20080508092102.GA32164@elte.hu> References: <87lk2mbcqp.fsf@basil.nowhere.org> <20080507114643.GR19219@parisc-linux.org> <87hcdab8zp.fsf@basil.nowhere.org> <1210214696.3453.87.camel@ymzhang> <20080508064340.GA27452@elte.hu> <1210230883.3453.127.camel@ymzhang> <20080508073924.GA30356@elte.hu> <1210236254.3453.137.camel@ymzhang> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <1210236254.3453.137.camel@ymzhang> User-Agent: Mutt/1.5.17 (2007-11-01) X-ELTE-VirusStatus: clean X-ELTE-SpamScore: -1.5 X-ELTE-SpamLevel: X-ELTE-SpamCheck: no X-ELTE-SpamVersion: ELTE 2.0 X-ELTE-SpamCheck-Details: score=-1.5 required=5.9 tests=BAYES_00 autolearn=no SpamAssassin version=3.2.3 -1.5 BAYES_00 BODY: Bayesian spam probability is 0 to 1% [score: 0.0000] Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org * Zhang, Yanmin wrote: > > disk_cp /mnt/shm > > disk_cp (1): cannot open /mnt/shm/tmpa.common > > disk1.c: No such file or directory > > > > [.. etc. a large stream of them .. ] > > > > system has 2GB of RAM and tmpfs mounted to the place where aim7 puts its > > work files. > My machine has 8GB. To simulate your environment, I reserve 6GB for > hugetlb, then reran the testing and didn't see any failure except: AIM > Multiuser Benchmark - Suite VII Run Beginning > > Tasks jobs/min jti jobs/min/task real cpu > 2000create_shared_memory(): can't create semaphore, pausing... > create_shared_memory(): can't create semaphore, pausing... that failure message you got worries me - it indicates that your test ran out of IPC semaphores. You can fix it via upping the semaphore limits via: echo "500 32000 128 512" > /proc/sys/kernel/sem could you check that you still get similar results with this limit fixed? note that once i've fixed the semaphore limits it started running fine here. And i see zero idle time during the run on a quad core box. here are my numbers: # on v2.6.26-rc1-166-gc0a1811 Tasks Jobs/Min JTI Real CPU Jobs/sec/task 2000 55851.4 93 208.4 793.6 0.4654 # BKL: sleep 2000 55402.2 79 210.1 800.1 0.4617 2000 55728.4 93 208.9 795.5 0.4644 # BKL: spin 2000 55787.2 93 208.7 794.5 0.4649 # so the results are the same within noise. I'll also check this workload on an 8-way box to make sure it's OK on larger CPU counts too. could you double-check your test? plus a tty tidbit as well, during the test i saw a few of these: Warning: dev (tty1) tty->count(639) != #fd's(638) in release_dev Warning: dev (tty1) tty->count(462) != #fd's(463) in release_dev Warning: dev (tty1) tty->count(274) != #fd's(275) in release_dev Warning: dev (tty1) tty->count(4) != #fd's(3) in release_dev Warning: dev (tty1) tty->count(164) != #fd's(163) in release_dev Ingo