Exactly constant timing in every iteration: cycles: out 667, in 305
processor : 0 vendor_id : GenuineIntel cpu family : 6 model : 8 model name : Celeron (Coppermine) stepping : 3 cpu MHz : 497.582 cache size : 128 KB fdiv_bug : no hlt_bug : no f00f_bug : no coma_bug : no fpu : yes fpu_exception : yes cpuid level : 2 wp : yes flags : fpu vme de pse tsc msr pae mce cx8 sep mtrr pge mca cmov pat pse36 mmx fxsr sse up bogomips : 996.21 clflush size : 32 On 12/12/07, Paolo Ornati <[EMAIL PROTECTED]> wrote: > On Wed, 12 Dec 2007 00:31:18 +0100 > Rene Herman <[EMAIL PROTECTED]> wrote: > > > > and on a PII 400 (Intel 440BX chipset) a constant: > > > > [EMAIL PROTECTED]:~/src/port80$ su -c ./port80 > > cycles: out 553, in 251 > > > > Results are (mostly) independent of compiler optimisation, but testing > with > > an -O2 compile should be most useful. Thanks! > > > > ### Core2 Duo 1.8 GHz ### > > X86_64 -m32 -O2: > > $ for i in `seq 5`; do sudo ./port80; sleep 1; done > cycles: out 1498, in 964 > cycles: out 1498, in 964 > cycles: out 1499, in 964 > cycles: out 1498, in 964 > cycles: out 1498, in 965 > > processor : 0 > vendor_id : GenuineIntel > cpu family : 6 > model : 15 > model name : Intel(R) Core(TM)2 CPU 6300 @ 1.86GHz > stepping : 6 > cpu MHz : 1864.805 > cache size : 2048 KB > physical id : 0 > siblings : 2 > core id : 0 > cpu cores : 2 > fpu : yes > fpu_exception : yes > cpuid level : 10 > wp : yes > flags : fpu vme de pse tsc msr pae mce cx8 apic sep mtrr pge mca cmov > pat > pse36 clflush dts acpi mmx fxsr sse sse2 ss ht tm pbe syscall nx lm > constant_tsc arch_perfmon pebs bts rep_good pni monitor ds_cpl vmx est tm2 > ssse3 cx16 xtpr lahf_lm > bogomips : 3731.82 > clflush size : 64 > cache_alignment : 64 > address sizes : 36 bits physical, 48 bits virtual > power management: > > [...] > > > -- > Paolo Ornati > Linux 2.6.24-rc4-g94545bad on x86_64 > -- > 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/ > -- 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/