Re: [patch] voluntary-preempt-2.6.8.1-P4

Lee Revell
2004-08-19T10:27:49Z

On Thu, 2004-08-19 at 04:56, Ingo Molnar wrote:
> > > > Any comments on the unmap_vmas issue?
> > >
> > > wli indicated he's working on the pagetable zapping critical section
> > > issue - wli?
>
> actually - the unmap_vmas() issue might be different. Could you change
> the '32' in this part of mm/memory.c:
>
> # define ZAP_BLOCK_SIZE \
> (voluntary_preemption ? (32 * PAGE_SIZE) : __ZAP_BLOCK_SIZE)
>
> to 16? Does that roughly halve the ~180 usec latency?
>

Yes, this takes care of it. Now the dominant latency is the 142us
latency from the via-rhine driver, which is fixed by using the driver
from -mm (specifically it's fixed in bk-netdev.patch).

Lee