Re: [linus:master] [shmem] a2e459555c: aim9.disk_src.ops_per_sec -19.0% regression

[Oliver Sang]

hi, Chuck Lever,

On Fri, Sep 08, 2023 at 02:43:22PM +0000, Chuck Lever III wrote:
> 
> 
> > On Sep 8, 2023, at 1:26 AM, kernel test robot <oliver.sang@xxxxxxxxx> wrote:
> > 
> > 
> > 
> > Hello,
> > 
> > kernel test robot noticed a -19.0% regression of aim9.disk_src.ops_per_sec on:
> > 
> > 
> > commit: a2e459555c5f9da3e619b7e47a63f98574dc75f1 ("shmem: stable directory offsets")
> > https://git.kernel.org/cgit/linux/kernel/git/torvalds/linux.git master
> > 
> > testcase: aim9
> > test machine: 48 threads 2 sockets Intel(R) Xeon(R) CPU E5-2697 v2 @ 2.70GHz (Ivy Bridge-EP) with 112G memory
> > parameters:
> > 
> > testtime: 300s
> > test: disk_src
> > cpufreq_governor: performance
> > 
> > 
> > In addition to that, the commit also has significant impact on the following tests:
> > 
> > +------------------+-------------------------------------------------------------------------------------------------+
> > | testcase: change | aim9: aim9.disk_src.ops_per_sec -14.6% regression                                               |
> > | test machine     | 48 threads 2 sockets Intel(R) Xeon(R) CPU E5-2697 v2 @ 2.70GHz (Ivy Bridge-EP) with 112G memory |
> > | test parameters  | cpufreq_governor=performance                                                                    |
> > |                  | test=all                                                                                        |
> > |                  | testtime=5s                                                                                     |
> > +------------------+-------------------------------------------------------------------------------------------------+
> > 
> > 
> > If you fix the issue in a separate patch/commit (i.e. not just a new version of
> > the same patch/commit), kindly add following tags
> > | Reported-by: kernel test robot <oliver.sang@xxxxxxxxx>
> > | Closes: https://lore.kernel.org/oe-lkp/202309081306.3ecb3734-oliver.sang@xxxxxxxxx
> 
> Hi, several weeks ago we requested that these tests be run
> again by the robot because they can't be run in environments
> I have available to me (the tests do not run on Fedora, and
> I don't have any big iron).
> 
> We wanted the tests rerun before the patch was committed.
> There was a deafening silence. So I assumed the work I did
> then to address the regression was successful, and the
> patches are now in upstream Linux.
> 
> This new report is disappointing.

I'm so sorry that I missed the test request for
https://lore.kernel.org/all/169030957098.157536.9938425508695693348.stgit@xxxxxxxxxxxxxxxxxxxxx/

just FYI, when this auto-bisect done,
head commit of linus/master: [65d6e954e37872fd9afb5ef3fc0481bb3c2f20f4] was
tested, it already includes
2be4f05af71bb libfs: Remove parent dentry locking in offset_iterate_dir()

in our tests, the regression still exists.


> 
> But, I'm still in a position where I can't run this test,
> and the results don't really indicate where the problem
> is. So I can't possibly address this issue.
> 
> Any suggestions, advice, or help would be appreciated.

if you have further fix patch, could you let us know? I will test it.

> 
> --
> Chuck Lever
> 
>