Re: [Myricom help #30221] Performance of Myrinet over TCP/IP

On Tue, 2004-09-07 at 12:52, Susan Blackford wrote:
> Hi, Craig,
> 
> On Tue, 2004-09-07 at 12:36, Craig Tierney wrote:
> > Has anyone tested sustainable bandwidth over using
> > IP emulations lately?  I remember in the past getting
> > measurements that were close to peak (> 200 MB/s) for
> > B cards.  However, I just tested mpptest over ch_p4 but
> > used the myrinet IP interface and I am only getting
> > 60 MB/s.  Is right?  The MTU is set to 9000 and I have
> > tried several different nodes.
> > 
> > I am using Fedora Core 1 with Linux-2.4.26.  The gm version
> > is 1.6.5.
> 
> For which size message did you see 60 MB/s?

I was running mpptest with "-size 0 65536 16384" several 
other settings with larger packets.  I never saw above
60 MB/s.

> 
> What's the value of the environment variable P4_SOCKBUFSIZE?

Not sure, I didn't change the default.  I realize there
are other kernel parameters I need to change for the TCP 
stack, but I did not try that yet.


> 
> Which architecture is this?

These are Xeon 2.2 Ghz.

> 
> And if you run netperf command, what level of performance do you see?
>   http://www.myri.com/cgi-bin/fom?file=84

I just ran netperf.  With packets over 1024 bytes, I
am seeing reasonable numbers, 1700 Mb/s.

I don't know what was up with mpptest.

Craig