serious networking (em) performance (ggate and NFS) problem

Claus Guttesen cguttesen at
Thu Nov 25 13:22:47 PST 2004

> > >ifnet and netisr queues.  You could also try
> setting net.isr.enable=1 to
> > >enable direct dispatch, which in the in-bound
> direction would reduce the
> > >number of context switches and queueing.  It
> sounds like the device driver
> > >has a limit of 256 receive and transmit
> descriptors, which one supposes is
> > >probably derived from the hardware limit, but I
> have no documentation on
> > >hand so can't confirm that.

It may not cast much light on the issue but I tried
setting net.isr.enable on to 1 on a nfs-server using
tcp on 5.3 RC3 copying between three clients. When
setting net.isr.enable to 0 the cpu-usage went up. The
server is running with this setting now and is being
mounted by 11 webservers. Using em-gb-card.


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