assigning interrupts

[Jeremy Chadwick]

On Thu, Nov 13, 2008 at 06:03:20PM +0800, Ronnel P. Maglasang wrote:
> Hi All,
>
> Is there a way to explicitly assign an interrupt
> of a device? I'm running on 6.3 and the two NICs
> share the same interrupt. Obviously this will affect
> the performance if the NICs are exposed to heavy network
> traffic.
>
> # vmstat -i
> interrupt                          total       rate
> <sniff>
> irq11: em0 vr0+                  1081099         77
> <sniff>
> Total                           16958562       1222
>
>
> Looking at the driver's code, I have the initial though
> that this is the place where I can modify.

This is the responsibility of the BIOS or ACPI configuration.  There is
no way to do this via OS software, as far as I know.

Try looking at the motherboard manual for what PCI levels (A/B/C/D)
share IRQs with what slot, then move cards around.

Otherwise, consider purchasing a motherboard that has an APIC (this is
not a typo) increasing the IRQ count to 256.

-- 
| Jeremy Chadwick                                jdc at parodius.com |
| Parodius Networking                       http://www.parodius.com/ |
| UNIX Systems Administrator                  Mountain View, CA, USA |
| Making life hard for others since 1977.              PGP: 4BD6C0CB |