As an FYI: Here's what a coworker of mine found when testing our new
Gigabit interface on our backupserver:

"I was able to see 200 MB/s between 2 GigabitEthernet cards residing on
a Sun
E450 and a Sun E420.  Both were in PCI slots with 66 MHz clock rate
capability. 
According to docs.sun.com, "individual PCI buses are capable of
sustained
throughput of 200 Mbytes per second".  So that matches what we've seen.

We monitored this using a TTCP tool I got from this web site:

http://www-iepm.slac.stanford.edu/monitoring/voip/ttcp.html";

    Barton Wold 
    United Defense L.P. 

He said that some tweaking of TCP buffers could theoretically increase
this to 210 per second.

Ryan Anderson


Andrew Steingruebl wrote:
> 
> I run the ucd-snmpd package on my backup servers and use cricket to graph the
> interface throughput.  It gives me pretty good stats on in/out traffic for the
> interface.  I only manage to push about 90mbit on a 100mbit interface, but I'm
> sure I could do more tuning to increase it.  I'm getting a gig-ethernet
> adapter soon to put into a 220, if I get stats I'll post them.
> 
> Oh, and have you thought about tuning your interface for better performance?
> Nice little article in adjusting TCP buffers, etc. in this months ;Login from
> Usenix.
> 
> - Andy
> 
> "Pearson, Kim (STP)" said:
> 
> >What is the best way to benchmark network throughput? We are using 2 Gigabit
> >ethernet ports on our NetBackup Master/Media server, and we are not seeing
> >the throughput we are expecting for backups. Since we stream multiple
> >classes to each drive, I'm inclined to believe that it's the network, not
> >the 8 DLT drives.  They sit idle a lot...shoe shining? We are using crude
> >copy scripts now to try to measure throughput - anyone got something better?
> >
> >HW - Sun E450, 2 Sun Gb PCI cards dedicated to the backup segment...
> >
> >Thanks!
> >
> >Kim
> >Kim Pearson
> >UNIX Team Lead
> >Guidant Corporation
> >kim.pearson AT guidant DOT com