Re: [LKP] [lkp] [f2fs] ec795418c4: fsmark.files_per_sec -36.3% regression

From: Huang\, Ying
Date: Mon Sep 26 2016 - 02:26:18 EST


Hi, Jaegeuk,

"Huang, Ying" <ying.huang@xxxxxxxxx> writes:

> Jaegeuk Kim <jaegeuk@xxxxxxxxxx> writes:
>
>> Hello,
>>
>> On Sat, Aug 27, 2016 at 10:13:34AM +0800, Fengguang Wu wrote:
>>> Hi Jaegeuk,
>>>
>>> > > >> > - [lkp] [f2fs] b93f771286: aim7.jobs-per-min -81.2% regression
>>> > > >> >
>>> > > >> > The disk is 4 12G ram disk, and setup RAID0 on them via mdadm. The
>>> > > >> > steps for aim7 is,
>>> > > >> >
>>> > > >> > cat > workfile <<EOF
>>> > > >> > FILESIZE: 1M
>>> > > >> > POOLSIZE: 10M
>>> > > >> > 10 sync_disk_rw
>>> > > >> > EOF
>>> > > >> >
>>> > > >> > (
>>> > > >> > echo $HOSTNAME
>>> > > >> > echo sync_disk_rw
>>> > > >> >
>>> > > >> > echo 1
>>> > > >> > echo 600
>>> > > >> > echo 2
>>> > > >> > echo 600
>>> > > >> > echo 1
>>> > > >> > ) | ./multitask -t &
>>> > > >>
>>> > > >> Any update on these 2 regressions? Is the information is enough for you
>>> > > >> to reproduce?
>>> > > >
>>> > > > Sorry, I've had no time to dig this due to business travel now.
>>> > > > I'll check that when back to US.
>>> > >
>>> > > Any update?
>>> >
>>> > Sorry, how can I get multitask binary?
>>>
>>> It's part of aim7, which can be downloaded here:
>>>
>>> http://nchc.dl.sourceforge.net/project/aimbench/aim-suite7/Initial%20release/s7110.tar.Z
>>
>> Thank you for the codes.
>>
>> I've run this workload on the latest f2fs and compared performance having
>> without the reported patch. (1TB nvme SSD, 16 cores, 16GB DRAM)
>> Interestingly, I could find slight performance improvement rather than
>> regression. :(
>> Not sure how to reproduce this.
>
> I think the difference lies on disk used. The ramdisk is used in the
> original test, but it appears that your memory is too small to setup the
> RAM disk for test. So it may be impossible for you to reproduce the
> test unless you can find more memory :)
>
> But we can help you to root cause the issue. What additional data do
> you want? perf-profile data before and after the patch?

Any update to this regression?

Best Regards,
Huang, Ying