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!
(AMD 1.8GHz Turion, running at 800MHz. ATI RS480 - Mitac 8350 mobo) [EMAIL PROTECTED]:~/Downloads$ gcc port80.c -o port80 [EMAIL PROTECTED]:~/Downloads$ sudo ./port80 cycles: out 1235, in 1207 [EMAIL PROTECTED]:~/Downloads$ sudo ./port80 cycles: out 1238, in 1205 [EMAIL PROTECTED]:~/Downloads$ sudo ./port80 cycles: out 1237, in 1209 [EMAIL PROTECTED]:~/Downloads$ gcc -O2 port80.c -o port80 [EMAIL PROTECTED]:~/Downloads$ sudo ./port80 cycles: out 1844674407370794, in 1844674407369408 [EMAIL PROTECTED]:~/Downloads$ sudo ./port80 cycles: out 1844674407370795, in 1844674407369404 [EMAIL PROTECTED]:~/Downloads$ sudo ./port80 cycles: out 1844674407370795, in 1844674407369409 [EMAIL PROTECTED]:~/Downloads$ sudo ./port80 cycles: out 1844674407370798, in 1844674407369407 [EMAIL PROTECTED]:~/Downloads$ cat /proc/cpuinfo processor : 0 vendor_id : AuthenticAMD cpu family : 15 model : 36 model name : AMD Turion(tm) 64 Mobile Technology ML-34 stepping : 2 cpu MHz : 800.000 cache size : 1024 KB fpu : yes fpu_exception : yes cpuid level : 1 wp : yes flags : fpu vme de pse tsc msr pae mce cx8 apic sep mtrr pge mca cmov pat pse36 clflush mmx fxsr sse sse2 syscall nx mmxext fxsr_opt lm 3dnowext 3dnow rep_good pni lahf_lm bogomips : 1592.87 TLB size : 1024 4K pages clflush size : 64 cache_alignment : 64 address sizes : 40 bits physical, 48 bits virtual power management: ts fid vid ttp tm stc Regards, Nigel -- 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/
