Message-ID: <53848490.6060001@vmware.com>
Date: Tue, 27 May 2014 15:26:56 +0300
From: Heikki Linnakangas <hlinnakangas@vmware.com>
Organization: VMware
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To: Albe Laurenz <laurenz.albe@wien.gv.at>,
 "pgsql-performance@postgresql.org" <pgsql-performance@postgresql.org>
Subject: Re: NFS, file system cache and shared_buffers
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On 05/27/2014 02:06 PM, Albe Laurenz wrote:
> I just learned that NFS does not use a file system cache on the client side.
>
> On the other hand, PostgreSQL relies on the file system cache for performance,
> because beyond a certain amount of shared_buffers performance will suffer.
>
> Together these things seem to indicate that you cannot get good performance
> with a large database over NFS since you can leverage memory speed.
>
> Now I wonder if there are any remedies (CacheFS?) and what experiences
> people have made with the performance of large databases over NFS.

I have no personal experience with NFS, but sounds like a 
higher-than-usual shared_buffers value would be good.

- Heikki


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