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<samba:parameter name="level2 oplocks"
                 context="S"
                 xmlns:samba="http://samba.org/common">
<listitem>
	<para>This parameter controls whether Samba supports
	level2 (read-only) oplocks on a share.</para>
		
	<para>Level2, or read-only oplocks allow Windows NT clients 
	that have an oplock on a file to downgrade from a read-write oplock 
	to a read-only oplock once a second client opens the file (instead 
	of releasing all oplocks on a second open, as in traditional, 
	exclusive oplocks). This allows all openers of the file that 
	support level2 oplocks to cache the file for read-ahead only (ie. 
	they may not cache writes or lock requests) and increases performance 
	for many accesses of files that are not commonly written (such as 
	application .EXE files).</para>

	<para>Once one of the clients which have a read-only oplock 
	writes to the file all clients are notified (no reply is needed 
	or waited for) and told to break their oplocks to &quot;none&quot; and 
	delete any read-ahead caches.</para>

	<para>It is recommended that this parameter be turned on to
	speed access to shared executables.</para>

	<para>For more discussions on level2 oplocks see the CIFS spec.</para>

	<para>Currently, if <link linkend="KERNELOPLOCKS"><parameter moreinfo="none">kernel 
	oplocks</parameter></link> are supported then level2 oplocks are 
	not granted (even if this parameter is set to <constant>yes</constant>). 
	Note also, the <link linkend="OPLOCKS"><parameter moreinfo="none">oplocks</parameter>
	</link> parameter must be set to <constant>yes</constant> on this share in order for 
	this parameter to have any effect.</para>

	<para>See also the <link linkend="OPLOCKS"><parameter moreinfo="none">oplocks</parameter>
	</link> and <link linkend="OPLOCKS"><parameter moreinfo="none">kernel oplocks</parameter>
	</link> parameters.</para>
		
	<para>Default: <command moreinfo="none">level2 oplocks = yes</command></para>
</listitem>
</samba:parameter>