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+<samba:parameter name="strict allocate"
+ context="S"
+ type="boolean"
+ xmlns:samba="http://www.samba.org/samba/DTD/samba-doc">
+<description>
+ <para>This is a boolean that controls the handling of
+ disk space allocation in the server. When this is set to <constant>yes</constant>
+ the server will change from UNIX behaviour of not committing real
+ disk storage blocks when a file is extended to the Windows behaviour
+ of actually forcing the disk system to allocate real storage blocks
+ when a file is created or extended to be a given size. In UNIX
+ terminology this means that Samba will stop creating sparse files.</para>
+
+ <para>This option is really designed for file systems that support
+ fast allocation of large numbers of blocks such as extent-based file systems.
+ On file systems that don't support extents (most notably ext3) this can
+ make Samba slower. When you work with large files over >100MB on file
+ systems without extents you may even run into problems with clients
+ running into timeouts.</para>
+
+ <para>When you have an extent based filesystem it's likely that we can make
+ use of unwritten extents which allows Samba to allocate even large amounts
+ of space very fast and you will not see any timeout problems caused by
+ strict allocate. With strict allocate in use you will also get much better
+ out of quota messages in case you use quotas. Another advantage of
+ activating this setting is that it will help to reduce file
+ fragmentation.</para>
+
+ <para>To give you an idea on which filesystems this setting might currently
+ be a good option for you: XFS, ext4, btrfs, ocfs2 on Linux and JFS2 on
+ AIX support unwritten extents. On Filesystems that do not support it,
+ preallocation is probably an expensive operation where you will see reduced
+ performance and risk to let clients run into timeouts when creating large
+ files. Examples are ext3, ZFS, HFS+ and most others, so be aware if you
+ activate this setting on those filesystems.</para>
+
+</description>
+
+<value type="default">no</value>
+</samba:parameter>