Re: [RFC/PATCHSET 00/14] perf report: Add support to accumulate hist periods (v2)

Ingo Molnar
2013-11-11T12:17:21Z

* Peter Zijlstra <peterz@infradead.org> wrote:

> On Wed, Nov 06, 2013 at 12:47:01PM +0100, Ingo Molnar wrote:
>
> > I'm not too worried about call-graph 'legacies': it generates such
> > huge perf.data files which is parsed so slowly at the moment that
> > there's very little user base ... Anyone who absolutely needs
> > call-graph profiling uses SysProf which performs well.
>
> Uhm, say what? I use it, and I don't use sysprof since that thing is
> totally not usable ;-)

You aren't a typical case at all! :-)

Just look back the example where Linus tried to use call-graph profiling
to profile a mild 60-seconds workload (a kernel build) and came away
reporting that his perf session locked up.

I think many other people ran into that performance problem. Those who are
using it must be using it for far shorter workloads.

Anyway, that's all fixed now, and I do think that call-graph profiling is
one of perf's killer features - I thought that from day 1 on when I
suggested to Frederic that it would be really important to implement it
;-)

Thanks,

Ingo