在 2013-01-15二的 10:34 +0800,Alex Shi写道: > On 01/14/2013 05:03 PM, li guang wrote: > >>> > > This corner case may occur after "[PATCH v3 03/22] sched: fix > >>> > > find_idlest_group mess logical" brought in the local sched_group bias, > >>> > > and assume balancing runs on cpux2. > >>> > > ideally, find_idlest_group should find the real idlest(this case: > >>> > > sgy), > >>> > > then, this patch is reasonable. > >>> > > > >> > > >> > Sure. but seems it is a bit hard to go down the idlest group. > >> > > >> > and the old logical is real cost too much, on my 2 socket NHM/SNB > >> > server, hackbench can increase 2~5% performance. and no clean > >> > performance on kbuild/aim7 etc. > > what about remove local group bias? > > > Any theory profit for non local group? Usually, bias toward local group > will has cache locality profit. >
but the disadvantage is miss correct balance sometime, if mostly like you said before it will bring in better performance, that's fine, I have no strong statistic to do more profound analysis. -- regards! li guang -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majord...@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/