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SubjectRe: [PATCH 1/3] Updated dynamic tick patches - Fix lost tick calculation in timer_pm.c
Hi!

> > 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.

Try running this from userspace (and watch for time going completely
crazy). Try it in mainline, too; it broke even vanilla some time
ago. Need to run as root.

Pavel

void
main(void)
{
int i;
iopl(3);
while (1) {
asm volatile("cli");
// for (i=0; i<20000000; i++)
for (i=0; i<1000000000; i++)
asm volatile("");
asm volatile("sti");
sleep(1);
}
}

--
if you have sharp zaurus hardware you don't need... you know my address
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