From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S965231AbWDOWaV (ORCPT ); Sat, 15 Apr 2006 18:30:21 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S932510AbWDOWaV (ORCPT ); Sat, 15 Apr 2006 18:30:21 -0400 Received: from smtp-out.google.com ([216.239.45.12]:22079 "EHLO smtp-out.google.com") by vger.kernel.org with ESMTP id S932509AbWDOWaU (ORCPT ); Sat, 15 Apr 2006 18:30:20 -0400 DomainKey-Signature: a=rsa-sha1; s=beta; d=google.com; c=nofws; q=dns; h=received:message-id:date:from:user-agent: x-accept-language:mime-version:to:cc:subject:references:in-reply-to: content-type:content-transfer-encoding; b=AaPJb7X9XxQeAURWqJ5wEXR+y+QKnOLz/CnkofplLDj8ZnITP4TkjFRw8Kx5X6NnR CRBBSgsdvr6iVDUClorvA== Message-ID: <444173EE.4060602@google.com> Date: Sat, 15 Apr 2006 15:30:06 -0700 From: "Martin J. Bligh" User-Agent: Mozilla Thunderbird 1.0.7 (X11/20051013) X-Accept-Language: en-us, en MIME-Version: 1.0 To: Andrew Morton CC: linux-kernel@vger.kernel.org, apw@shadowen.org Subject: Re: Clear performance regression on reaim7 in 2.6.15-git6 References: <4441452F.3060009@google.com> <20060415141744.042231a8.akpm@osdl.org> <44416616.10908@google.com> <20060415145227.5d1249bd.akpm@osdl.org> In-Reply-To: <20060415145227.5d1249bd.akpm@osdl.org> Content-Type: text/plain; charset=ISO-8859-1; format=flowed Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org Andrew Morton wrote: > "Martin J. Bligh" wrote: > >>drilling down into the results directories can get you the command line, >> looks like "reaim -f workfile.short -s 1 -e 10 -i 2" to me. Buggered if >> I can recall what that did though. >> >> (http://test.kernel.org/abat/20229/004.reaim.test/results/cmdline) >> >> I *think* it's only ia32 NUMA boxes, at least as far as I can see from >> a quick poke around. Which would make me guess at scheduler code. Gitweb >> would be nice to use, but it doesn't tag the -git snapshots, AFAICS, >> which is a real shame. Nor does the git snapshot include the git tag, >> as far as I know. Grrrr. I guess I'll download the snapshots and diff >> them, and try to pull out the sched changes by hand. Much suckage. > > > The diffstat for 2.6.15-git5 -> 2.6.15-git6 is at > http://www.zip.com.au/~akpm/linux/patches/stuff/2 - only a single line > changed in sched.c: > > diff -uNr 2.6.15-git5/kernel/sched.c 2.6.15-git6/kernel/sched.c > --- 2.6.15-git5/kernel/sched.c 2006-04-15 14:10:43.000000000 -0700 > +++ 2.6.15-git6/kernel/sched.c 2006-04-15 14:10:52.000000000 -0700 > @@ -4386,6 +4386,7 @@ > } while_each_thread(g, p); > > read_unlock(&tasklist_lock); > + mutex_debug_show_all_locks(); > } Hmm. whilst it's probably not that call, it does look like mutex debugging. Look at the profiles from reaim between -git5 and -git6: before: http://test.kernel.org/abat/20115/004.reaim.test/profiling/profile.text after: http://test.kernel.org/abat/20229/004.reaim.test/profiling/profile.text 1262 kfree 3.5056 820 mutex_lock_interruptible 164.0000 752 __mutex_lock_slowpath 0.8754 43 schedule 0.0284 35 _spin_lock 2.3333 25 debug_mutex_set_owner 0.1613 23 debug_mutex_add_waiter 0.1586 /me hugs his huge stacks of data. -------------------------------- config DEBUG_MUTEXES bool "Mutex debugging, deadlock detection" default y depends on DEBUG_KERNEL help This allows mutex semantics violations and mutex related deadlocks (lockups) to be detected and reported automatically. -------------------------------- Hmmm. Who the hell thought defaulting that to 'y' was a good plan???? It's still broken in 17-rc1 ... will send you a patch in a sec. M. PS. Jeff Garzik pointed out there *are* git tags for each -git snapshot http://www.kernel.org/pub/linux/kernel/v2.6/snapshots/patch-2.6.17-rc1-git11.id which is really helpful.