From mboxrd@z Thu Jan  1 00:00:00 1970
From: "David S. Miller" <davem@davemloft.net>
Subject: Re: bad TSO performance in 2.6.9-rc2-BK
Date: Wed, 29 Sep 2004 14:52:46 -0700
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To: John Heffner <jheffner@psc.edu>
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On Wed, 29 Sep 2004 17:51:22 -0400 (EDT)
John Heffner <jheffner@psc.edu> wrote:

> I managed to get a tcpdump of one flow.  I accidentally deleted it, but
> from memory what I saw was it ramped up to large virtual segments, then
> got a partial ack for it (all but the last real segment -- delayed ack
> here) then later after the full ack got back sent one small segment.
> This segment was acked, but it never seemed to recognize this ack and
> repeatedly retransmitted it after timeouts.  (Generating the retrans_out
> leaked messages when the d-sacks came back.)
> 
> I can't conveniently get a backtrace of the crash right now.

I can get one now, thanks for the trace description it's
a good clue.