The benefit of TSO is not throughput, but CPU utilization. Throughput
increase is usually a side effect because of better PCI DMA behavior (eg.
large PCI transfers are better). Are you seeing a CPU utilization decrease?
On Friday 21 January 2005 01:01 pm, Rick Jones wrote:
> Is it indeed supposed to be the case that the on the wire behaviour of TCP
> with
> TSO on/off is supposed to be the same? I'm seeing some cases (netperf
> TCP_STREAM 2.6.10 sending to HP-UX 11.23) where the throughput differences
> are
> >= 10 MB/s on an e1000 card (TSO being slower). I've got lots of netperf
> and
> tcpdump but thought I'd ask first before dumping it onto the list. Actually,
> i'll probably have to put it up on the net somewhere since it is O(200MB) in
> total (although I have a smaller point example).
>
> sincerely,
>
> rick jones
>
>
>
--
Jon Mason
jdmason@xxxxxxxxxx
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