From mboxrd@z Thu Jan  1 00:00:00 1970
From: David Howells <dhowells@redhat.com>
Subject: Re: Cachefiles question
Date: Fri, 08 May 2009 15:11:07 +0100
Message-ID: <9390.1241791867@redhat.com>
References: <20090508125425.GK18351@ics.muni.cz>
Cc: dhowells@redhat.com, linux-fsdevel@vger.kernel.org,
	nfsv4@linux-nfs.org
To: Lukas Hejtmanek <xhejtman@ics.muni.cz>
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Lukas Hejtmanek <xhejtman@ics.muni.cz> wrote:

> what is fscache newly added into mainline supposed to do?
> 
> I thought it is used as writeback cache and read cache for network file
> systems. But it appears that it does not do any writeback and it seems it
> caches only few reads.

It only caches files on NFS that are opened for reading at the moment due to
coherency issues.

> however, after the build is complete:
> /opt/fscache# du -sm
> 2	.

Is there anything in dmesg?

And can you check /proc/fs/fscache/stats?

David