Re: [PATCH] perf stat: Pass PERF_STAT_RUN environment variable for each run

From: Namhyung Kim
Date: Thu Jul 17 2014 - 04:31:45 EST


Hi Peter,

On Thu, Jul 17, 2014 at 5:26 PM, Peter Zijlstra <peterz@xxxxxxxxxxxxx> wrote:
> On Thu, Jul 17, 2014 at 05:21:06PM +0900, Namhyung Kim wrote:
>> When perf stat runs multiple times via -r option, it's sometimes
>> useful for a workload to know which run it executing. So pass new
>> PERF_STAT_RUN environment variable to the workload for each run
>> (starting from 1).
>
> This seems counter intuitive, runs should be _identical_ otherwise
> there's no point. That means the workload should very much _not_ know
> these things.

But I think it can be useful if a workload wants to save logfiles
based on the iteration number for example. If it doesn't want, it can
just ignore. :)

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/