[ntp:questions] NTP + kernel frequency

Jan Ceuleers janspam.ceuleers at skynet.be
Sat Nov 10 08:48:58 UTC 2007


Jan Ceuleers wrote:
> Per Hedeland wrote:
>> 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 yields 41Hz on my Via C7 machine (which has frequency scaling and 
> runs a 2.6.22-based kernel) while it's idle, and a higher number (e.g. 
> 90Hz) while it's doing something. It yields 100Hz on a Soekris 4801 
> running 2.4.31.
> 
> In other words, this method doesn't seem to be entirely reliable, 
> possibly as a side effect of frequency scaling.

Found this method:

# getconf CLK_TCK
100

Works on both machines.




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