On Mon, 2007-10-29 at 17:37 +0800, Zhang, Yanmin wrote: > On Mon, 2007-10-29 at 10:22 +0800, Zhang, Yanmin wrote: > > On Fri, 2007-10-26 at 13:23 +0200, Ingo Molnar wrote: > > > * Zhang, Yanmin <[EMAIL PROTECTED]> wrote: > > > > > > > I tested 2.6.24-rc1 on my x86_64 machine which has 2 quad-core > > > > processors. > > > > > > > > Comparing with 2.6.23, aim7 has about -30% regression. I did a bisect > > > > and found patch > > > > http://git.kernel.org/?p=linux/kernel/git/torvalds/linux-2.6.git;a=commitdiff;h=b5869ce7f68b233ceb81465a7644be0d9a5f3dbb > > > > > > > > caused the issue. > > > > > > weird, that's a commit diff - i.e. it changes no code. > > I got the tag from #git log. As for above link, I just added prior http > > address, > > so readers could check the patch by clicking. > > > > > > > > > kbuild/SPECjbb2000/SPECjbb2005 also has big regressions. On my another > > > > tigerton machine (4 quad-core processors), SPECjbb2005 has more than > > > > -40% regression. I didn't do a bisect on such benchmark testing, but I > > > > suspect the root cause is like aim7's. > > > > > > these two commits might be relevant: > > > > > > 7a6c6bcee029a978f866511d6e41dbc7301fde4c > > I did a quick testing. This patch has no impact. > > > > > 95dbb421d12fdd9796ed153853daf3679809274f > > Above big patch doesn't include this one, which means if I do > > 'git checkout b5869ce7f68b233ceb81465a7644be0d9a5f3dbb', the kernel doesn't > > include > > 95dbb421d12fdd9796ed153853daf3679809274f. > > > > > > > > but a bisection result would be the best info. > > I will do a bisect between 2.6.23 and tag > > 9c63d9c021f375a2708ad79043d6f4dd1291a085. > I ran git bisect with kernel version as the tag. It looks like git will > be crazy sometimes. So I checked ChangeLog and used the number tag to replace > the kernel version and retested it. > > It looks like at least 2 patches were responsible for the regression. I'm > doing sub-bisect now. > > I could find aim7 regression on all my testing machines although the > regression > percentage is different. > > Machine regression > 8-core stoakley 30% > 16-core tigerton 6% > tulsa(dual-core+HT, 16 logical cpu) 20% sub-bisecting captured patch 38ad464d410dadceda1563f36bdb0be7fe4c8938(sched: uniform tunings) caused 20% regression of aim7.
The last 10% should be also related to sched parameters, such like sysctl_sched_min_granularity. -yanmin - To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to [EMAIL PROTECTED] More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
