* Waiman Long <Waiman.Long@xxxxxx> wrote: > Testing done on a 4-socket Westmere-EX boxes with 40 cores (HT off) > showed the following performance data (average kops/s) with various > load factor (number of pause instructions) used in the critical > section using an userspace mutex microbenchmark. > > Threads Load Waiting Futex Spinning Futex %Change > ------- ---- ------------- -------------- ------- > 256 1 6894 8883 +29% > 256 10 3656 4912 +34% > 256 50 1332 4358 +227% > 256 100 792 2753 +248% > 10 1 6382 4838 -24% > 10 10 3614 4748 +31% > 10 50 1319 3900 +196% > 10 100 782 2459 +214% > 2 1 7905 7194 -9.0% > 2 10 4556 4717 +3.5% > 2 50 2191 4167 +90% > 2 100 1767 2407 +36% So the numbers look interesting - but it would be _really_ important to provide noise/sttdev figures in a sixth column as well (denoted in percentage units, not in benchmark units), so that we know how significant a particular speedup (or slowdown) is. Thanks, Ingo -- To unsubscribe from this list: send the line "unsubscribe linux-api" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
