On Sun, 2013-06-30 at 23:29 +0200, Peter Zijlstra wrote: > Yeah, who'd have thought that putting stuff in the syscall path would've > made syscalls more expensive ;-)
(careful, you'll injure my innocence, Santa and the Tooth Fairy exist!) > But yeah, that's a _lot_ more expensive.. I'd not be surprised if more > people would find that objectionable. Distros may want some hot patching or _something_ before doing the usual new=turn-it-on thing. Per trusty (spelled with 'c') old Q6600, the cost is pretty darn high. -regress is my ~light regression testing config, carried forward from 3.6.32...master across all intervening trees. -regressx is plus CONFIG_RCU_USER_QS=y CONFIG_CONTEXT_TRACKING_FORCE=y -regressxx is plus full dynticks taskset -c 3 pipe-test 1 2.6.32-regress 654.5 Khz 1.000 3.10.0-regress 652.1 Khz .996 1.000 3.10.0-regressx 476.8 Khz .728 .731 3.10.0-regressxx 275.6 Khz .421 .422 tbench 2.6.32-regress 327.502 MB/sec 1.000 3.10.0-regress 319.621 MB/sec .975 1.000 3.10.0-regressx 292.894 MB/sec .894 .916 3.10.0-regressxx 243.738 MB/sec .744 .762 netperf TCP_RR 2.6.32-regress 104041.84 Trans/sec 1.000 3.10.0-regress 94961.34 Trans/sec .912 1.000 3.10.0-regressx 82383.33 Trans/sec .791 .867 3.10.0-regressxx 61527.59 Trans/sec .591 .647 -- 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/
