On Wednesday 22 March 2006 19:32, Paolo Pisati wrote:
> On Wed, Mar 22, 2006 at 03:45:12PM -0500, John Baldwin wrote:
> > This is going out to the I/O APIC and writing a bit to mask the
> > interrupt until the handler has run. Is he using a kernel that
> > has SMP enabled? If so, turning SMP off might make things
> > slightly better.
>
> 7.x:
> SMP is on, PREEMPTION if off
You probably want preemption on to minimize latency. If this is a
UP machine, you should turn SMP off. It might be interesting to
compare using 7.x without APIC as well, since you are not using
APIC on 4.x.
--
John Baldwin <jhb@FreeBSD.org> <>< http://www.FreeBSD.org/~jhb/
"Power Users Use the Power to Serve" = http://www.FreeBSD.org