Re: [Regression or Fix]perf: profiling stats sigificantly changed for aio_write/read(ext4) between 6.7.0-rc1 and 6.6.0

[Namhyung Kim]

On Wed, Nov 15, 2023 at 3:00 AM David Wang <00107082@xxxxxxx> wrote:
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> At 2023-11-15 18:32:41, "Peter Zijlstra" <peterz@xxxxxxxxxxxxx> wrote:
> >
> >Namhyung, could you please take a look, you know how to operate this
> >cgroup stuff.
> >
>
> More information,  I run the profiling with 8cpu machine on a SSD with ext4 filesystem :
>
> # mkdir /sys/fs/cgroup/mytest
> # echo $$ > /sys/fs/cgroup/mytest/cgroup.procs
> ## Start profiling targeting cgroup /sys/fs/cgroup/mytest   on another terminal
> # fio --randrepeat=1 --ioengine=libaio --direct=1 --name=test  --bs=4k --iodepth=64 --size=1G --readwrite=randrw  --runtime=600 --numjobs=4 --time_based=1
>
> I got a feeling that f06cc667f7990 would decrease total samples by 10%~20% when profiling IO benchmark within cgroup.

Oh sorry, I missed this message.  Can you please share the
command line and the output?

Thanks,
Namhyung