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Comments: In-reply-to Rick Macklem <rmacklem@uoguelph.ca>
	message dated "Fri, 05 Mar 2010 17:01:59 -0500."
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Date: Sat, 06 Mar 2010 09:09:57 +0200
From: Daniel Braniss <danny@cs.huji.ac.il>
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Cc: stable@freebsd.org, freebsd-fs@freebsd.org,
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	rwatson@freebsd.org, Jeremy Chadwick <freebsd@jdc.parodius.com>
Subject: Re: mbuf leakage with nfs/zfs? 
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[...]
> > but it didn't help, it's not triggered
> >
> 
> Hmm, well that's the only place I could see in replay.c that could leak
> (and it's a pretty straightforward piece of code). This is getting
> interesting. Just to confirm where we currently are...
> 
> - replay cache disabled --> no leak
> - replay cache enabled (with or without the above patch) --> leak
> 
yes and yes.

> I'll take another look, but I doubt the leak is in replay.c so... maybe
> a reply from the cache is somehow handled incorrectly and that causes the
> leak elsewhere? (Just a random hunch at this point.)
> 
it works ok in 7.2, so it would be interesting to compare changes ...

> > Thanks for the explanation on the cache, things are begining to make sense.
> > If I understand, the reason for this cache is to prevent re-applying an
> > already performed rpc, which could lead to data corruption
> >
> 
> Yep, you've got it. It is basically a bandaid for the poor transport
> semantics provided by UDP.
> 
> Having fun with this one. Thanks for the help, rick
> 
I'm glad :-)

	danny