[OpenIndiana-discuss] How to test ethernet throughput?

[Richard Elling]

On May 22, 2012, at 1:41 PM, Robbie Crash wrote:

> Gaming iperf you can get close to theoretical maximums on wire connections,
> but if you're just on a 10/100 network looks liek you've got everything
> working properly.  Real world performance (for me) sits at around 400Mb/sec
> for medium (4-100MB) files, 600Mb/sec for large (100MB+) files. Files under
> 4MB are effectively instantaneous.

For short runs, the TCP window size guess has a big impact. If it is not quite right
on both the client and server (too big or too small), then there will be reduced 
performance until it adjusts. This really isn't gaming, it is the reason why long runs
are preferred for benchmarks. Or, as many benchmarkers will attest, a run < 1 minute
isn't useful.
 -- richard

> 
> #default
> $ ./iperf -c thoth
> ------------------------------------------------------------
> Client connecting to thoth, TCP port 5001
> TCP window size: 8.00 KByte (default)
> ------------------------------------------------------------
> [396] local 192.168.2.8 port 55100 connected with 192.168.2.24 port 5001
> [ ID] Interval       Transfer     Bandwidth
> [396]  0.0-10.0 sec   265 MBytes   222 Mbits/sec
> 
> #Forcing settings
> $ ./iperf -N -w 9M -c thoth
> ------------------------------------------------------------
> Client connecting to thoth, TCP port 5001
> TCP window size: 9.00 MByte
> ------------------------------------------------------------
> [388] local 192.168.2.8 port 55313 connected with 192.168.2.24 port 5001
> [ ID] Interval       Transfer     Bandwidth
> [388]  0.0-10.1 sec  1.05 GBytes   896 Mbits/sec
> 
> 
> 
> 
> On Mon, May 21, 2012 at 10:18 AM, Gary Mills <gary_mills at fastmail.fm> wrote:
> 
>> On Fri, May 18, 2012 at 08:38:09AM -0500, Gary Mills wrote:
>>> I'm just finishing a driver for the Atheros AR8131 and AR8132 ethernet
>>> devices.  I'm ready now to test it under load.  What's available in
>>> OpenIndiana for this purpose?  I couldn't see anything in the
>>> repository that seemed suitable.  I don't need to bring the interface
>>> up to maximum throughput, but I'd at least like to be sure that
>>> nothing breaks when it has a reasonable load.
>> 
>> Thanks to all who responded.  Most of you recommended `iperf'.  That's
>> what I used.  Not being a network expert, I didn't know what options
>> to use, but with the defaults I was able to push many packets through
>> this interface in both directions.  The driver worked nicely.  I got a
>> bandwith of about 94 Mbits/sec, three times that of the wireless
>> interface.  That's all I needed.
>> 
>> --
>> -Gary Mills-            -refurb-                -Winnipeg, Manitoba,
>> Canada-
>> 
>> _______________________________________________
>> OpenIndiana-discuss mailing list
>> OpenIndiana-discuss at openindiana.org
>> http://openindiana.org/mailman/listinfo/openindiana-discuss
>> 
> 
> 
> 
> -- 
> Seconds to the drop, but it seems like hours.
> 
> http://www.eff.org/
> <http://www.eff.org/>http://creativecommons.org/
> _______________________________________________
> OpenIndiana-discuss mailing list
> OpenIndiana-discuss at openindiana.org
> http://openindiana.org/mailman/listinfo/openindiana-discuss

--
ZFS Performance and Training
Richard.Elling at RichardElling.com
+1-760-896-4422