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

David Ahern
2013-11-11T14:45:16Z

On 11/11/13, 5:19 AM, Ingo Molnar wrote:
>
> In what way is call-graph profiling utilized typically?
>
> Is it system-wide, i.e. something like:
>
> perf record -a -g sleep 10
>
> ? If yes then that would explain why scalability problems rarely surfaced,
> it takes a longer user-space profile to get to the event counts where
> scalability started hurting.

Both. But not time periods long enough to generate GB sized files
(limitations in the product). I get various reports of hung commands
(usually perf-not terminated properly (now fixed) or the file is
corrupted on transfer), but noone has complained to me about perf-report
appearing to hang or for 20-30 minutes to generate a result.

David