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

Frederic Weisbecker
2013-11-11T15:45:14Z

On Mon, Nov 11, 2013 at 02:56:37PM +0100, Ingo Molnar wrote:
>
> * Frederic Weisbecker <fweisbec@gmail.com> wrote:
>
> > On Mon, Nov 11, 2013 at 01:13:52PM +0100, Ingo Molnar wrote:
> > >
> > > It's not an irrelevant feature at all! :-)
> > >
> > > It's just that for any sort of longer profile it was pretty
> > > difficult/frustrating to use, which I think held back adoption.
> > >
> > > That performance problem got fixed now by you and Namhyung, so I think
> > > we'll see even wider adoption of call-graph profiling...
> >
> > Ah I see now. At the time Linus reported his issue, I had the feeling
> > his usecase was a bit "extreme", but I actually have no idea how far
> > perf can be used given that I'm mostly used to short benchmarks,
> > typically hackbench, perf bench sched messaging et al. Thing is I don't
> > use it enough for my real usecases :)
>
> Well, it's a bit of a catch-22: if there are severe scalability problems
> for a usecase then people won't use it because they cannot use it. So
> developers should usually try to over-measure things and go for extreme
> uses and such.

Agreed :)