![]() | |||||||||||||
Messages in this thread |
Rene Herman wrote: > On 12-12-07 01:09, Alejandro Riveira Fernández wrote: > >>>> On my AMD 3800 X2 (2000MHz) ULi M1697 2.6.24-rc5 i get: >>>> >>>> cycles: out 1844674407370808, in 1844674407369087 >>>> >>>> It is not constant but variations are not significant afaics >>> Eh, oh, I guess you need to compile as a 32-bit binary... >> >> I tried without -O2 as Nigel Cunningham... >> >> cycles: out 1562, in 865 >> cycles: out 1562, in 866 >> cycles: out 1555, in 858 >> cycles: out 1562, in 866 >> >> With -m32 -O2 >> cycles: out 1566, in 876 >> cycles: out 1555, in 865 >> cycles: out 1594, in 931 >> cycles: out 1559, in 874 > > Great, thanks much for reporting. Sort of interesting in itself that > without -O2 you do still get correct results on 64-bit but for some > other time. > > You're the first one to go significantly below 1 us it seems. Make sure the CPU is actually running at full frequency. It probably would have been better to have used gettimeofday() around a sufficiently big loop, so that we would have gotten wall time rather than cycles. -hpa -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/ | ||||||||||||
| Last update: 2007-12-12 22:21 [from the cache] ©2003-2008 | |||||||||||||