manpages: document 'fsc' mount option

Document the newly added local caching feature using FS-Cache. This patch
could be queued and considered once the local caching patches gets merged
upstream.

Signed-off-by: Suresh Jayaraman <sjayaraman@suse.de>

1 files changed, 17 insertions, 0 deletions

diff --git a/doc/mount.cifs.8.xml b/doc/mount.cifs.8.xml
index 4937550..2200746 100644
--- a/doc/mount.cifs.8.xml
+++ b/doc/mount.cifs.8.xml
@@ -534,6 +534,23 @@ permissions in memory that can't be stored on the server. This information can d
                 maximum wsize currently allowed by CIFS is 57344 (fourteen
                 4096 byte pages)</para></listitem>
 	</varlistentry>
+	<varlistentry>
+		<term>fsc</term>
+
+		<listitem><para>Enable local disk caching using FS-Cache
+		for cifs. This option could be useful to improve performance
+		on a slow link, heavily loaded server and/or network
+		where reading from the disk is faster than reading from the
+		server (over the network). This could also impact the
+		scalability positively as the number of calls to the server
+		are reduced. But, be warned that local caching is not suitable
+		for all workloads, for e.g., read-once type workloads. So
+		you need to consider carefully the situation/workload before
+		using this option.
+		NOTE: You also need to have cachefilesd daemon installed and
+		running to make the cache operational.
+                </para></listitem>
+	</varlistentry>
 	 <varlistentry>
                 <term>--verbose</term>
                 <listitem><para>Print additional debugging information for the mount. Note that this parameter must be specified before the -o. For example:</para><para>mount -t cifs //server/share /mnt --verbose -o user=username</para></listitem>