Re: [snitzer:cel-nfsd-next-6.12-rc5] [nfsd] b4be3ccf1c: fsmark.app_overhead 92.0% regression

[Oliver Sang <oliver.sang@intel.com>]

hi, Chuck Lever,

On Mon, Dec 16, 2024 at 05:23:48PM -0500, Chuck Lever wrote:
> On 12/5/24 9:33 PM, Oliver Sang wrote:
> > hi, Chuck Lever,
> > 
> > On Thu, Dec 05, 2024 at 10:37:10AM -0500, Chuck Lever wrote:
> > 
> > [...]
> > 
> > > 
> > > Earlier this week I thought I had the full set of patches to
> > > test and could just apply them on v6.13-rc1, but it turns out
> > > that I don't have them all yet. There are one or two that I
> > > broke while trying to prepare for v6.12, and I've misplaced
> > > Jeff's originals.
> > > 
> > > I will let you know when that branch is ready for a retest.
> > > Sorry for the noise!
> > 
> > Not at all! always our great pleasure that we can supply any help.
> > 
> > got it. just wait your notification. thanks!
> 
> The series currently in the nfsd-testing branch is complete and stable
> enough for you to benchmark.

FYI. we compared the branch tip with v6.13-rc3, the fsmark.app_overhead
regression are less now. while fsmark.files_per_sec keeps not being impacted.

if bisect can succeed to spot out one commit, we will also send out a report.

=========================================================================================
compiler/cpufreq_governor/disk/filesize/fs2/fs/iterations/kconfig/nr_files_per_directory/nr_threads/rootfs/sync_method/tbox_group/test_size/testcase:
  gcc-12/performance/1HDD/4K/nfsv4/btrfs/1x/x86_64-rhel-9.4/1fpd/1t/debian-12-x86_64-20240206.cgz/fsyncBeforeClose/lkp-icl-2sp6/40M/fsmark

commit:
  v6.13-rc3
  8d5b7358ea7c0 ("nfsd: add shrinker to reduce number of slots allocated per session")

       v6.13-rc3 8d5b7358ea7c07b69c44f0af21e
---------------- ---------------------------
         %stddev     %change         %stddev
             \          |                \
   2790150 ± 52%     -60.6%    1099116 ±120%  numa-meminfo.node1.FilePages
    697551 ± 52%     -60.6%     274783 ±120%  numa-vmstat.node1.nr_file_pages
      1176 ± 71%   +2210.3%      27185 ±247%  sched_debug.cpu.max_idle_balance_cost.stddev
      2882            -7.1%       2677        vmstat.system.cs
   3064384           +57.8%    4834169        fsmark.app_overhead
     18.58            -0.2%      18.54        fsmark.files_per_sec
     53429           -17.3%      44169        fsmark.time.voluntary_context_switches
      2805            -7.4%       2598        perf-stat.i.context-switches
      2800            -7.4%       2594        perf-stat.ps.context-switches
   1750049            -1.2%    1729157        proc-vmstat.numa_hit
   1617582            -1.3%    1596589        proc-vmstat.numa_local
      2.03 ±  2%      +5.5%       2.14        time.system_time
     53429           -17.3%      44169        time.voluntary_context_switches
      0.80 ± 11%      -0.3        0.52 ± 56%  perf-profile.calltrace.cycles-pp.tcp_write_xmit.__tcp_push_pending_frames.tcp_sendmsg_locked.tcp_sendmsg.sock_sendmsg
      0.80 ± 11%      -0.2        0.59 ± 39%  perf-profile.calltrace.cycles-pp.__tcp_push_pending_frames.tcp_sendmsg_locked.tcp_sendmsg.sock_sendmsg.svc_tcp_sendmsg
      0.39 ± 23%      -0.2        0.19 ± 53%  perf-profile.children.cycles-pp.__close
      0.39 ± 20%      -0.2        0.20 ± 47%  perf-profile.children.cycles-pp.__x64_sys_close
      0.14 ± 15%      -0.1        0.06 ± 79%  perf-profile.children.cycles-pp.syscall_return_via_sysret

> 
> 
> -- 
> Chuck Lever