shared irqs and performance

Subhro subhro.kar at
Tue Sep 14 21:51:53 PDT 2004

The card won't be facing any stability problems. And there is no
reason why you should force the card to another IRQ because modern
motherboards DOES allow IRQ sharing and there is no performance hits
for it.


On Tue, 14 Sep 2004 18:56:18 -0600, Gary Aitken <garya at> wrote:
> On my 4.10 system, I added in a third ethernet device.
> However, I see from dmesg that the irq assigned is shared with my
> scsi controller:
> de1: <Digital 21041 Ethernet> port 0xf880-0xf8ff mem
>   0xfdfffc00-0xfdfffc7f irq 9 at device 16.0 on pci0
> bt0: <Buslogic Multi-Master SCSI Host Adapter> port 0xfcec-0xfcef
>   irq 9 at device 17.0 on pci0
> Since the driver was already present, things went ok, in the sense
> that the system booted and scsi devices still work.
> 1.  Will this work reliably (I haven't actually hooked anything
>     to the new network card yet)?
> 2.  Even if it does work, I assume it would be better to force
>     it to an unused irq for performance reasons?
> Thanks,
> Gary
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Subhro Sankha Kar
School of Information Technology
Block AQ-13/1 Sector V
ZIP 700091

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