Re: [RFT] Port 0x80 I/O speed

From: Jesper Juhl
Date: Wed Dec 12 2007 - 16:33:05 EST


On 12/12/2007, Rene Herman <rene.herman@xxxxxxxxx> 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.
>

root@dragon:/home/juhl# uname -a
Linux dragon 2.6.24-rc3-g2ffbb837 #7 SMP PREEMPT Mon Nov 19 22:16:27
CET 2007 i686 AMD Athlon(tm) 64 X2 Dual Core Processor 4400+
AuthenticAMD GNU/Linux
root@dragon:/home/juhl# cat /proc/cpuinfo
processor : 0
vendor_id : AuthenticAMD
cpu family : 15
model : 35
model name : AMD Athlon(tm) 64 X2 Dual Core Processor 4400+
stepping : 2
cpu MHz : 2200.000
cache size : 1024 KB
fdiv_bug : no
hlt_bug : no
f00f_bug : no
coma_bug : no
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 ht syscall nx mmxext
fxsr_opt lm 3dnowext 3dnow pni lahf_lm cmp_legacy ts fid vid ttp
bogomips : 4401.67
clflush size : 64

processor : 1
vendor_id : AuthenticAMD
cpu family : 15
model : 35
model name : AMD Athlon(tm) 64 X2 Dual Core Processor 4400+
stepping : 2
cpu MHz : 2200.000
cache size : 1024 KB
fdiv_bug : no
hlt_bug : no
f00f_bug : no
coma_bug : no
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 ht syscall nx mmxext
fxsr_opt lm 3dnowext 3dnow pni lahf_lm cmp_legacy ts fid vid ttp
bogomips : 4399.52
clflush size : 64

root@dragon:/home/juhl# for i in $(seq 1 10); do ./port80 ; sleep 1 ; done
cycles: out 1839, in 1715
cycles: out 1728, in 1604
cycles: out 1762, in 1714
cycles: out 1770, in 1722
cycles: out 1759, in 1723
cycles: out 1764, in 1723
cycles: out 1762, in 1712
cycles: out 1761, in 1723
cycles: out 1771, in 1715
cycles: out 1770, in 1709


--
Jesper Juhl <jesper.juhl@xxxxxxxxx>
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