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From: Vivek Khera <vivek@khera.org>
Date: Mon, 23 May 2005 17:17:16 -0400
To: freebsd-amd64@freebsd.org
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Cc: freebsd-stable@freebsd.org
Subject: Re: Manipulating disk cache (buf) settings
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On May 23, 2005, at 1:44 PM, John-Mark Gurney wrote:

> This is incorrect...  FreeBSD merged the vm and buf systems a while  
> back,
> so all of memory is used as a disk cache..  The buf cache is still  
> used
> for filesystem meta data (and for pending writes of files, but  
> those buf's
> reference the original page, not local storage)...
>

Cool... So what would you recommend telling an application like  
Postgres what the cache size is?  All of RAM?  That seems unlikely  
given much of the ram is used for other things.  Is there no upper  
bound in how much RAM will be used for the cache?

Vivek Khera, Ph.D.
+1-301-869-4449 x806