Messages in this thread | | | From | Con Kolivas <> | Subject | Re: gettimeofday order of magnitude slower with pmtimer, which is default | Date | Tue, 21 Mar 2006 14:09:50 +1100 |
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On Tue, 21 Mar 2006 01:59 pm, OGAWA Hirofumi wrote: > Yes. However, if machines uses buggy chip, I guessed TSC/PIT would be > more proper as time source.
Oh yes but there has been an epidemic of timer problems (fast/slow, lost ticks etc) lately meaning the pm timer is being relied upon more and more.
> But probably you are right, timer_pit.c > seems more slow usually (it uses many I/O port). > > I'll remove unlikely(), and also will remove "Use other timer source" > from warning.
Suggesting another timer source is ok in the warning I believe given massive amounts of wasted cpu.
> BTW, this patch is still quick hack.
Understood. Perhaps having an indirect function call set to either good_pmtmr() or bad_pmtmr() after checking would be preferable to a variable that is checked on each function call despite never changing.
> At least, we would need to check the ICH4 which says in comment. > However, I couldn't find the PM-Timer Errata in ICH4 spec update. > > Do you/anyone know about a ICH4 error?
Not personally but my ICH4 pm timer seems to work very well whereas Andi's apparently similar chipset exhibits terrible problems.
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