Messages in this thread | | | Date | Thu, 13 Jan 2022 10:17:04 +0800 | From | Oliver Sang <> | Subject | Re: [ucounts] 59ec71575a: will-it-scale.per_process_ops -10.3% regression |
| |
Hi Eric,
On Wed, Jan 12, 2022 at 01:08:23PM -0600, Eric W. Biederman wrote: > kernel test robot <oliver.sang@intel.com> writes: > > > Greeting, > > > > FYI, we noticed a -10.3% regression of will-it-scale.per_process_ops due to commit: > > > I am having a bit of a challenge reading this report. Does the -10.3% > mean that will-it-scale.per_process_ops is performing 70873 operations > per second instead of 78995 aka -10.3% fewer operations per second?
yes
> > The per-profile.self-cycles-pp.do_dec_rlimits_put_ucounts now takes +2.6 > more cycles, and perf-profile.self.cycles.pp.inc_rlimit_get_ucounts now > takes +3.8 more cycles. > > Which if I read this correctly is a regression report about two > functions taking 3 or 4 cycles more after the code was rearranged inside > of them. > > Is that correct? Is this a regression report saying those two functions > are taking a few cycles more which leads to > will-it-scale.per_process_ops not being able to perform as many > operations per second?
yes
> > Given the change in the commit mentioned I think this is all down to a > bug fix causing the code to be rearranged and a compiler optimizations. > > I don't see much room to do anything about this.
got it. this is a bug fix. Thanks for explanation!
> > Eric >
| |