From owner-freebsd-fs@FreeBSD.ORG  Fri Oct 14 17:23:49 2005
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To: rick@snowhite.cis.uoguelph.ca
From: Jim Rees <rees@umich.edu>
In-Reply-To: rick@snowhite.cis.uoguelph.ca, Fri, 14 Oct 2005 12:55:49 EDT
Date: Fri, 14 Oct 2005 13:23:48 -0400
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Cc: fs@freebsd.org
Subject: Re: FreeBSD NFS server not responding to TCP SYN packets from
	Linux/SunOS clients 
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Tcp always throws away retransmissions.  Doesn't matter whether the data is
still in the receive socket queue or not.  The nfs server will never see
replayed requests as a result of tcp retransmission.

  The problem is "how do you make sure the nfsd threads don't start a
  request if the disk I/O subsystem is backlogged".

Isn't this simply a matter of choosing the right number of nfsd threads?