Re: bdflush/rpciod high CPU utilization, profile does not make sense

Greg Banks
2005-04-12T01:04:57Z

On Tue, 2005-04-12 at 01:42, Jakob Oestergaard wrote:
> Yes, as far as I know - the Broadcom Tigeon3 driver does not have the
> option of enabling/disabling RX polling (if we agree that is what we're
> talking about), but looking in tg3.c it seems that it *always*
> unconditionally uses NAPI...

I've whined and moaned about this in the past, but for all its
faults NAPI on tg3 doesn't lose packets. It does cause a huge
increase in irq cpu time on multiple fast CPUs. What irq rate
are you seeing?

I did once post a patch to make NAPI for tg3 selectable at
configure time.
http://marc.theaimsgroup.com/?l=linux-netdev&m=107183822710263&w=2

> No dropped packets... I wonder if the tg3 driver is being completely
> honest about this...

At one point it wasn't, since this patch it is:
http://marc.theaimsgroup.com/?l=linux-netdev&m=108433829603319&w=2

Greg.
--
Greg Banks, R&D Software Engineer, SGI Australian Software Group.
I don't speak for SGI.