Re: [PATCH 1/2] perf sched: Introduce timehist command - v2

From: Namhyung Kim
Date: Mon Dec 02 2013 - 02:59:20 EST


On Sun, 1 Dec 2013 17:23:14 -0700, David Ahern wrote:
> 'perf sched timehist' provides an analysis of scheduling events.
>
> Example usage:
> perf sched record -- sleep 1
> perf sched timehist
>
> By default it shows the individual schedule events, including the time between
> sched-in events for the task, the task scheduling delay (time between wakeup
> and actually running) and run time for the task:
>
> time cpu task name[tid/pid] b/n time sch delay run time
> ------------- ---- -------------------- --------- --------- ---------
> 79371.874569 [11] gcc[31949] 0.014 0.000 1.148
> 79371.874591 [10] gcc[31951] 0.000 0.000 0.024
> 79371.874603 [10] migration/10[59] 3.350 0.004 0.011
> 79371.874604 [11] <idle> 1.148 0.000 0.035
> 79371.874723 [05] <idle> 0.016 0.000 1.383
> 79371.874746 [05] gcc[31949] 0.153 0.078 0.022
> ...
>
> Times are in msec.usec.

Hmm.. I'm not sure this is right. It probably confuse users since
timehist_time_str() still uses "sec.usec" format and it looks not
natural for me to use "msec".

Yeah, I see perf stat uses "msec.usec" for result of clock events but
AFAICT it also shows the unit explicitly. And perf stat -I uses
"sec.nsec" format and perf script also uses "sec.usec" format so there's
a little consistency here.

I think this "msec.usec" format fits well for the scheduling events but
in general "sec.usec" format looks better IMHO.

Thanks,
Namhyung
--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at http://vger.kernel.org/majordomo-info.html
Please read the FAQ at http://www.tux.org/lkml/