Re: hwo to adjust interrupt?

Ming Zhang
2005-08-12T13:14:46Z

On Fri, 2005-08-12 at 09:14 +0200, Arjan van de Ven wrote:
> On Thu, 2005-08-11 at 18:31 -0400, Ming Zhang wrote:
> > I have this eth1 and aic7xxx share 1 interrupt thus have impact on
> > performance, anyway i can change it? thx!
>
> realistically, either you need to find a bios setting tweak, or you need
> to move one of the two to a different pci slot in the machine.
>

i could not find any bios setting in the bios. it is a dell sc420. i
will try to move card around and see what happen. thx!

>
> (Not that it's a big problem, sharing irqs on a pci system isn't too big
> a deal)
>

i use it as my iscsi testbed so the sole activities are disk&network.
that is why i am worrying about it.

do you think it is ok to share? i think at least kernel need to find 1
irq handler to process the handler, then it have 1/2 chance (roughly
assume 1 network interrupt corresponding to 1 storage io interrupt, of
course this is not true in reality) to find that this is not the right
one and then reload another handler? i guess this will be critical when
# is huge like this. (i ran might 10 minutes with iometer on an iscsi
target.)

16: 1330261 0 IO-APIC-level eth1, aic7xxx

Ming