On Mon, 17 Mar 2003, Ben Greear wrote:
> Ralph Doncaster wrote:
[...]
> > Currently the box in question is running a 67% system load with ~40kpps.
> > Here's the switch port stats that the 2 3c905cx cards are plugged into:
> >
> > 5 minute input rate 36143000 bits/sec, 8914 packets/sec
> > 5 minute output rate 54338000 bits/sec, 10722 packets/sec
> > -
> > 5 minute input rate 50585000 bits/sec, 12445 packets/sec
> > 5 minute output rate 34326000 bits/sec, 9596 packets/sec
>
> When using larger packets, NAPI doesn't have much effect.
So I should just give up on Linux and go with FreeBSD?
http://info.iet.unipi.it/~luigi/polling/
> Have you tried routing with simple routing tables to see if that
> speeds anything up?
No, but I did read through a bunch of the route-cache code and even with
the dynamic hashtable size introduced in recent 2.4 revs, it looks very
ineficient for core routing. I'd expect a speedup with a small routing
table, but then it would be useless as a core router in my network.
> Could also try an e100 or Tulip NIC. Those usually work pretty
> good... Or, could use an e1000 GigE NIC...
If I can get confirmation that under similar conditions the e1000 performs
significantly better, then I'll go that route.
> It's also possible that you are just reaching the limit of your
> system.
The NAPI docs imply 144kpps is easily attainable on lesser hardware than
mine. Also I can't see bandwidth being the issue as I'm moving
<25Mbytes/sec over the PCI bus. I should be able to do more than double
that before I have to worry about PCI saturation.
-Ralph
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