Re: [lkp-robot] [mm, mlock, vmscan] 9c4e6b1a70: stress-ng.hdd.ops_per_sec -7.9% regression

From: Shakeel Butt
Date: Sun Feb 25 2018 - 17:03:44 EST


On Sun, Feb 25, 2018 at 6:44 AM, kernel test robot
<xiaolong.ye@xxxxxxxxx> wrote:
>
> Greeting,
>
> FYI, we noticed a -7.9% regression of stress-ng.hdd.ops_per_sec due to commit:
>
>
> commit: 9c4e6b1a7027f102990c0395296015a812525f4d ("mm, mlock, vmscan: no more skipping pagevecs")
> https://git.kernel.org/cgit/linux/kernel/git/torvalds/linux.git master
>
> in testcase: stress-ng
> on test machine: 88 threads Intel(R) Xeon(R) CPU E5-2699 v4 @ 2.20GHz with 128G memory
> with following parameters:
>

Hi Xiaolong,

Is there a way I can get the output of "perf record -a -g" running in
parallel to the actual test on this machine. As I have mentioned
before I am not able to reproduce this issue. However I am trying to
repro on a VM with 4 vcpus and 4 GiB memory and I don't see any
difference. I am suspecting that it may repro on a larger machine but
I don't have access to one.

thanks,
Shakeel