The revised code is faster on Intel Atom N270 by around 15% (results below typical of several runs): $ ./586test ; ./x86test Result: a9993e36 4706816a ba3e2571 7850c26c 9cd0d89d Expected:a9993e36 4706816a ba3e2571 7850c26c 9cd0d89d 500000000 bytes: 4.981760 s Result: a9993e36 4706816a ba3e2571 7850c26c 9cd0d89d Expected:a9993e36 4706816a ba3e2571 7850c26c 9cd0d89d 500000000 bytes: 4.323324 s $ cat /proc/cpuinfo processor : 0 vendor_id : GenuineIntel cpu family : 6 model : 28 model name : Intel(R) Atom(TM) CPU N270 @ 1.60GHz stepping : 2 cpu MHz : 800.000 cache size : 512 KB physical id : 0 siblings : 2 core id : 0 cpu cores : 1 apicid : 0 initial apicid : 0 fdiv_bug : no hlt_bug : no f00f_bug : no coma_bug : no 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 clflush dts acpi mmx fxsr sse sse2 ss ht tm pbe nx constant_tsc arch_perfmon pebs bts pni dtes64 monitor ds_cpl est tm2 ssse3 xtpr pdcm lahf_lm bogomips : 3191.59 clflush size : 64 power management: processor : 1 vendor_id : GenuineIntel cpu family : 6 model : 28 model name : Intel(R) Atom(TM) CPU N270 @ 1.60GHz stepping : 2 cpu MHz : 800.000 cache size : 512 KB physical id : 0 siblings : 2 core id : 0 cpu cores : 1 apicid : 1 initial apicid : 1 fdiv_bug : no hlt_bug : no f00f_bug : no coma_bug : no 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 clflush dts acpi mmx fxsr sse sse2 ss ht tm pbe nx constant_tsc arch_perfmon pebs bts pni dtes64 monitor ds_cpl est tm2 ssse3 xtpr pdcm lahf_lm bogomips : 3191.91 clflush size : 64 power management: -- Brian Ristuccia brian@xxxxxxxxxxxxx -- To unsubscribe from this list: send the line "unsubscribe git" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html