Subject: Re: TCP performance problem/question
To: Mark Allman <>
From: Dave Huang <>
List: tech-net
Date: 03/31/2000 11:38:16
On Fri, 31 Mar 2000, Mark Allman wrote:
> The stack does fast retransmit.  I can't tell if that is the problem
> here or not because it looks like the trace has been snipped.
> But....

It's snipped above and below the part I quoted, but I didn't remove
anything from within the trace.

> >  [ ack ack ack ]
> [[ I am not sure what the snipped ACKs look like.  If they have an
>    updated advertised window they are probably reseting the dupack
>    counter. ]]

That was just my way of saying that the remote side is sending more
ACKs... I didn't actually remove any ACKs.

> It would be interesting to see the entire trace (the binary version
> would be especially nice).  What concerns me about this is the
> apparent long delay between receiving the last ACK and
> retransmitting the missing segment.  (I say "apparent" because there

I didn't save a binary version, and I can't seem to duplicate the
problem with a 1.4X kernel. I'll try reverting to my previous kernel and
see if the problem happens again though.
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