Re: e1000 full-duplex TCP performance well below wire speed

From: Bill Fink
Date: Thu Jan 31 2008 - 12:36:57 EST


Hi Bruce,

On Thu, 31 Jan 2008, Bruce Allen wrote:

> > I see similar results on my test systems
>
> Thanks for this report and for confirming our observations. Could you
> please confirm that a single-port bidrectional UDP link runs at wire
> speed? This helps to localize the problem to the TCP stack or interaction
> of the TCP stack with the e1000 driver and hardware.

Yes, a single-port bidirectional UDP test gets full GigE line rate
in both directions with no packet loss.

[bill@chance4 ~]$ nuttcp -f-beta -Itx -u -Ru -w2m 192.168.6.79 & nuttcp -f-beta -Irx -r -u -Ru -w2m 192.168.6.79
tx: 1187.0078 MB / 10.04 sec = 992.0550 Mbps 19 %TX 7 %RX 0 / 151937 drop/pkt 0.00 %loss
rx: 1187.1016 MB / 10.03 sec = 992.3408 Mbps 19 %TX 7 %RX 0 / 151949 drop/pkt 0.00 %loss

-Bill
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