[ofa-general] Re: [PATCH 0/9 Rev3] Implement batching skb API and support in IPoIB

Stephen Hemminger
2007-08-24T03:34:25Z

On Thu, 23 Aug 2007 18:38:22 -0400
jamal <hadi@cyberus.ca> wrote:

> On Thu, 2007-23-08 at 15:30 -0700, David Miller wrote:
> > From: jamal <hadi@cyberus.ca>
> > Date: Thu, 23 Aug 2007 18:04:10 -0400
> >
> > > Possibly a bug - but you really should turn off TSO if you are doing
> > > huge interactive transactions (which is fair because there is a clear
> > > demarcation).
> >
> > I don't see how this can matter.
> >
> > TSO only ever does anything if you accumulate more than one MSS
> > worth of data.
>
> I stand corrected then.
>
> cheers,
> jamal
>

For most normal Internet TCP connections, you will see only 2 or 3 packets per TSO
because of ACK clocking. If you turn off delayed ACK on the receiver it
will be even less.

A current hot topic of research is reducing the number of ACK's to make TCP
work better over asymmetric links like 3G.

--
Stephen Hemminger <shemminger@linux-foundation.org>