On Fri, 15 Oct 2004, Jason Lunz wrote:
> ganesh.venkatesan@xxxxxxxxx said:
> > + This sets the InterruptThrottleRate to 3000 interrupts/sec for
> > the
> > + first, second, and third instances of the driver. The range of
> > 2000 to
> > + 3000 interrupts per second works on a majority of systems and is
> > a
> > + good starting point, but the optimal value will be
> > platform-specific.
> > + If CPU utilization is not a concern, use RX_POLLING (NAPI) and
> > default
> > + driver settings.
> I don't understand this bit. Isn't the point of NAPI to disable rx
> interrupts entirely, and only gather as many frames from the driver as
> CPU time permits? That's supposed to limit network-rx CPU usage, not
> increase it as the above paragraph implies.
In my experience (on Altix systems, so that experience may be
somewhat atypical), NAPI results in few (2-7) packets processed
per interrupt, so the interrupt rate (and CPU utilization) can be
very high. Interrupt coalescence is much better in both of these