Re: [PATCH V4 00/17] Stitch LBR call stack (Perf Tools)

From: Arnaldo Carvalho de Melo
Date: Fri Apr 17 2020 - 17:54:08 EST


Em Fri, Apr 17, 2020 at 05:47:49PM -0400, Liang, Kan escreveu:
>
>
> On 4/17/2020 1:48 PM, Arnaldo Carvalho de Melo wrote:
> > Em Thu, Mar 19, 2020 at 01:25:00PM -0700, kan.liang@xxxxxxxxxxxxxxx escreveu:
> > > For a simple test case tchain_edit with 43 depth of call stacks.
> > > perf record --call-graph lbr -- ./tchain_edit
> > > perf report --stitch-lbr

> > > Without --stitch-lbr, perf report only display 32 depth of call stacks.
> > > With --stitch-lbr, perf report can display all 43 depth of call stacks.
> > > The depth of call stacks increase 34.3%.

> > > Correspondingly, the processing time of perf report increases 39%,
> > > Without --stitch-lbr: 11.0 sec
> > > With --stitch-lbr: 15.3 sec

> > Next time provide the full test proggie, I had to expand those ... to
> > reproduce your results,

> Sure, I will do so in the future.

> > all I have is in perf/core, some patches are
> > still to be processed, will continue later, have to stop now, see:

> > https://git.kernel.org/pub/scm/linux/kernel/git/acme/linux.git/commit/?id=13cfba6b741ff

> > For my testing, looks really great!

> Thanks for the testing. :)

My pleasure.

BTW everything is in there by now.

- Arnaldo