On Sat, 10 Nov 2007 00:38:23 +0000, Per Hedeland wrote:
> In article <[EMAIL PROTECTED]>
> [EMAIL PROTECTED] (Hal Murray) writes:
>>
>>>I known now, in the "recen"t kernel the internal frequency will be to
>>>250 Mhz...
>>>With my gentoo it's not a problem for me because i make myself my kernel
>>>... but if i take Mandriva or a another distribution how find this
>>>values ?
>>
>>I assume you mean the scheduling clock which would be 250 Hz rather than
>>MHz.
>>
>>One way is to look in the kernel souces.
>>
>>Another way is to measure it. Write a program that usleeps for a
>>microsecond and see how long it really takes. (Do it in a loop for 1000
>>tries and print out a histogram.)
>
> On Linux, a simpler way can be to look at /proc/interrupts - e.g.
> (probably Linux-version- and possibly config-specific):
>
> $ (cat /proc/interrupts; sleep 10; cat /proc/interrupts) | \
> awk '/timer/{prev=now; now=$2} END{printf "%dHz\n", int((now-prev)/10)}'
This doesn't work on multi-CPU systems.
: cat /proc/interrupts |grep timer
0: 129602418 129428516 IO-APIC-edge timer
You need to sum across all CPUs. A bit more complex:
-------------- snip --------------
#!/usr/bin/perl -w
$cpus=`grep -c processor /proc/cpuinfo`;
$_=`grep timer /proc/interrupts`; @prev=split();
sleep 10;
$_ =`grep timer /proc/interrupts`; @now =split();
for (1..$cpus) { $prev+=$prev[$_]; $now+=$now[$_]}
printf "%dHz\n", int(($now-$prev)/10);
-------------- snip --------------
--
2007/11/13:11:39:48UTC Slackware Linux 2.4.32
up 29 days, 23:31, 6 users, load average: 2.18, 2.26, 2.25
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