HZ of 1024

Andriy Gapon avg at icyb.net.ua
Thu Dec 14 03:37:41 PST 2006


Peter and all,

I am playing with an idea of using RTC/IRQ8 instead of 8254 timer/IRQ0
to drive system hard clock. Due to the nature of RTC, if I got it
correctly, I think I will have to use HZ of 1024 (or some reasonable
divisor of it).
I've accidentally noticed that 1024 was used as a default value of hz on
amd64 systems for a while, but then it was changed to use 1000.
I've read the cvs commit logs about some interference with stat clock
and/or prof clock, but I couldn't dig up any detailed information about
this.
Could you please share your experience about hz=1024 and advise what I
should look for ? Maybe you even have some ideas on how to eliminate or
reduce the interference ?

Thank you.

-- 
Andriy Gapon



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