* Borislav Petkov <b...@alien8.de> wrote:
> On Thu, Feb 02, 2017 at 01:10:54PM +0100, Borislav Petkov wrote:
> > Now on to run the same thing on a bigger bulldozer.
>
> It looks differently on the bigger box:
>
> before:
>
> Performance counter stats for 'make -s -j17 bzImage' (3 runs):
> 143.807894000 seconds time elapsed
> ( +- 0.89% )
>
> Performance counter stats for 'make -s -j17 bzImage' (3 runs):
> 147.109189694 seconds time elapsed
> ( +- 0.49% )
If there's any doubt about the validity of the measurement I'd suggest doing:
perf stat -a --sync --repeat 3 ...
... so that there's no perf overhead and skew from the many processes of a
kernel
build workload, plus the --sync should reduce IO related noise.
Or:
perf stat --null --sync --repeat 3 ...
... will only measure elapsed time, but will do that very precisely and with
very
little overhead.
Thanks,
Ingo
