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From: David Miller <davem@davemloft.net>
To: jheffner@psc.edu
Cc: netdev@vger.kernel.org
Subject: MTU probing bug?
Date: Tue, 25 Jul 2006 00:17:44 -0700 (PDT)	[thread overview]
Message-ID: <20060725.001744.26930215.davem@davemloft.net> (raw)


John, have a look at this code in tcp_write_timeout():

		mss = min(sysctl_tcp_base_mss,
		          tcp_mtu_to_mss(sk, icsk->icsk_mtup.search_low)/2);
		mss = max(mss, 68 - tp->tcp_header_len);

That first line looks like it should be a max() instead
of a min().

tcp_base_mss is the smallest MSS we should use, therefore
we should make sure the "mss" is at least that large.

It's also possible that I misread the intention of this code :) From
what I read, it is trying to half the MSS in use and adjust the MTU
search low point to be based upon this new value.


             reply	other threads:[~2006-07-25  7:17 UTC|newest]

Thread overview: 4+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2006-07-25  7:17 David Miller [this message]
2006-07-25 13:56 ` MTU probing bug? John Heffner
2006-07-25 21:42   ` David Miller
2006-07-26  1:53     ` John Heffner

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