On Fri, Apr 20, 2007 at 10:47:57AM +1000, Con Kolivas wrote: > On Friday 20 April 2007 01:01, Con Kolivas wrote: > > This then allows the maximum rr_interval to be as large as 5000 > > milliseconds. > > Just for fun, on a core2duo make allnoconfig make -j8 here are the build time > differences (on a 1000HZ config) machine: > > 16ms: > 53.68user 4.81system 0:34.27elapsed 170%CPU (0avgtext+0avgdata 0maxresident)k > > 1ms: > 56.73user 4.83system 0:36.03elapsed 170%CPU (0avgtext+0avgdata 0maxresident)k > > 5000ms: > 52.88user 4.77system 0:32.37elapsed 178%CPU (0avgtext+0avgdata 0maxresident)k > > For the record, 16ms is what SD v0.43 would choose as the default value on > this hardware. A load with a much lower natural context switching rate than a > kernel compile, as you said Nick, would show even greater discrepancy in > these results. > > Fun eh? Note these are not for any comparison with anything else; just to > show > the effect rr_interval changes have on throughput.
Yeah very interesting, thanks. I was sure that a more modern CPU and/or one with more cache (in this case, both!) would show bigger differences even on kbuild. In this case, 16ms -> infinite results in almost 6% performance improvement. - 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/