Re: [PATCH 1/3] Updated dynamic tick patches - Fix lost tick calculationin timer_pm.c

[Peter Williams]

Lee Revell wrote:
> On Wed, 2005-08-31 at 22:42 +0530, Srivatsa Vaddagiri wrote:
>
> > With this patch, time had kept up really well on one particular
> > machine (Intel 4way Pentium 3 box) overnight, while
> > on another newer machine (Intel 4way Xeon with HT) it didnt do so
> > well (time sped up after 3 or 4 hours). Hence I consider this
> > particular patch will need more review/work.
>
>
> Are lost ticks really that common?  If so, any idea what's disabling
> interrupts for so long (or if it's a hardware issue)?  And if not, it
> seems like you'd need an artificial way to simulate lost ticks in order
> to test this stuff.

In my experience, turning off DMA for IDE disks is a pretty good way to 
generate lost ticks :-)

Peter
--
Peter Williams                                   pwil3058@xxxxxxxxxxxxxx

"Learning, n. The kind of ignorance distinguishing the studious."
 -- Ambrose Bierce
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