Rene Herman wrote: > Good day. > > Would some people on x86 (both 32 and 64) be kind enough to compile and > run the attached program? This is about testing how long I/O port access > to port 0x80 takes. It measures in CPU cycles so CPU speed is crucial in > reporting. > > Posted a previous incarnation of this before, buried in the outb 0x80 > thread which had a serialising problem. This one should as far as I can > see measure the right thing though. Please yell if you disagree... > > For me, on a Duron 1300 (AMD756 chipset) I have a constant: > > [EMAIL PROTECTED]:~/src/port80$ su -c ./port80 > cycles: out 2400, in 2400 > > 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! > > Rene. > [EMAIL PROTECTED] jkosin]# cat /proc/cpuinfo processor : 0 vendor_id : GenuineIntel cpu family : 6 model : 7 model name : Pentium III (Katmai) stepping : 3 cpu MHz : 499.156 cache size : 512 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 bogomips : 996.14
[EMAIL PROTECTED] jkosin]# ./a.out cycles: out 683, in 299 [EMAIL PROTECTED] jkosin]# ./a.out cycles: out 683, in 299 [EMAIL PROTECTED] jkosin]# ./a.out cycles: out 683, in 299 [EMAIL PROTECTED] jkosin]# -- Scanned by ClamAV - http://www.clamav.net -- 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/
