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Date: Thu, 20 Dec 2007 03:59:55 +1100 (EST)
From: Bruce Evans <brde@optusnet.com.au>
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Cc: freebsd-net@freebsd.org, freebsd-stable@freebsd.org,
	Bruce Evans <brde@optusnet.com.au>
Subject: Re: Packet loss every 30.999 seconds
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On Wed, 19 Dec 2007, David G Lawrence wrote:

>> Try it with "find / -type f >/dev/null" to duplicate the problem almost
>> instantly.
>
>   FreeBSD used to have some code that would cause vnodes with no cached
> pages to be recycled quickly (which would have made a simple find
> ineffective without reading the files at least a little bit). I guess
> that got removed when the size of the vnode pool was dramatically
> increased.

It might still.  The data should be cached somewhere, but caching it
in both the buffer cache/VMIO and the vnode/inode is wasteful.

I may have been only caching vnodes for directories.  I switched to
using a find or a tar on /home/ncvs/ports since that has a very high
density of directories.

Bruce