Messages in this thread | | | Date | Mon, 31 Oct 2016 12:19:16 -0600 (MDT) | From | Thomas Gleixner <> | Subject | Re: [LKP] [lkp] [x86/platform/UV] 71854cb812: will-it-scale.per_thread_ops -2.3% regression |
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On Mon, 31 Oct 2016, Fengguang Wu wrote: > On Fri, Oct 28, 2016 at 12:37:45AM +0200, Thomas Gleixner wrote: > > I have no explanation for this either, but you really should try to figure > > out what's going on here. > > Xiaolong, how about doing a small debug patch (a WARN_ONCE() line may > be enough) to verify whether the code path is executed? > > It'd also help to compare vmlinux according to Thomas' reasoning: > > > The only difference between plain rc1 and rc + this patch is the resulting > > text size and therefor some other unrelated stuff moving to different > > places in memory which has some yet to figure out side effects.
So one other thing you might try is using rc3 as a base line and then revert the patch in question on top of rc3 and see whether that weird behaviour persists.
> > From bisect POV, the below graphs show the user_time and system_time > are clearly and consistently different before/after commit 71854cb812. > So this commit must impacted something.
I agree. I just have no idea what happens.
Thanks,
tglx
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