Em Fri, Jul 25, 2014 at 01:34:26PM +0200, Jiri Olsa escreveu: > On Thu, Jul 24, 2014 at 06:34:51PM -0300, Arnaldo Carvalho de Melo wrote: > > I think both changes are OK, but should be split in different patches, > right, I'll split it
Thanks! > > [root@zoo /]# perf stat -r 5 perf report --no-ordered-samples > /dev/null > > 101,171,572,553 instructions # 1.10 insns per > > cycle > > 30.249514999 seconds time elapsed > > ( +- 0.48% ) > > [root@zoo /]# perf stat -r 5 perf report --ordered-samples > /dev/null > > 105,982,144,263 instructions # 1.04 insns per > > cycle > > 32.636483981 seconds time elapsed > > ( +- 0.41% ) > so those 2 extra seconds is the ordering time, right? sounds ok Yeah, but I think its worth investigating if using it is a strict requirement in all cases, i.e. is it possible to receive out of order events when sampling on a single CPU? Or a single CPU socket with a coherent time source? etc. Providing a way to disable this ordering to be used in corner cases where it is not a strict requirement and the volume of samples is so high that reducing processing time like shown above seems to be a sensible thing to do. We're in the business of optimizing stuff, huh? :-) - Arnaldo -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to [email protected] More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
