Subject: Re: Performance of Alteon/Tigon Gigabit Ethernet cards
To: Hal Murray <firstname.lastname@example.org>
From: Manuel Bouyer <email@example.com>
Date: 01/30/2001 22:55:53
On Mon, Jan 29, 2001 at 10:49:49PM -0800, Hal Murray wrote:
> I'm running my collection of network testing/bashing scritps. Performance
> is "strange" but I can't put my finger on it yet.
> I'm running 1.5 on Miatas (600au) and XP1000s.
> Are there are any known problems/quirks? Or parameters I should
> tweak? Anybody managed to get good results on this gear?
> Any good/bad results with jumbo packets?
> The symptoms are that sometimes things are reasonable and then, an
> hour later when I run the same script again, it doesn't work very
> For example, a TCP request-response test with short data blocks takes
> either 200 microseconds or 10 miliseconds. It works within reason
> for blocks over 20K bytes - throughput is 230 megabits.
> I'm guessing there is some internal mode/state that I'm getting into
> that's "bad". Obviously, I don't know what it is yet.
> One of my tests is a simple UDP-blast test that often overloads the
> receive side. I see things like this in the /var/log/messages.
> Jan 29 18:16:16 ruby /netbsd: WARNING: mclpool limit reached; increase NMBCLUSTERS
> Jan 29 18:16:16 ruby /netbsd: ti0: cluster allocation failed -- packet dropped!
> Jan 29 18:16:36 ruby last message repeated 867 times
> Jan 29 18:16:36 ruby /netbsd: fpa0: can't alloc cluster
> Jan 29 18:16:36 ruby /netbsd: ti0: cluster allocation failed -- packet dropped!
> Jan 29 18:16:49 ruby last message repeated 800 times
> Jan 29 18:17:09 ruby last message repeated 412 times
> Jan 29 18:17:21 ruby /netbsd: WARNING: mclpool limit reached; increase NMBCLUSTERS
A yes, you need to increase NMBCLUSTERS
I think on an alpha you can increase it dynamically with
sysctl -w kern.mbuf.nmbclusters=x
You may want to try 4096 or 8192 for x.
I have a netgear in a DS20, it works pretty well.
Manuel Bouyer <firstname.lastname@example.org>