From 37115f91aebec9c846e54790c6bcf433ae35888a Mon Sep 17 00:00:00 2001 From: Björn Jacke Date: Wed, 17 Feb 2010 23:03:32 +0100 Subject: s3:docs: add some advice for usage of strict allocate --- docs-xml/smbdotconf/tuning/strictallocate.xml | 24 ++++++++++++++++++------ 1 file changed, 18 insertions(+), 6 deletions(-) (limited to 'docs-xml') diff --git a/docs-xml/smbdotconf/tuning/strictallocate.xml b/docs-xml/smbdotconf/tuning/strictallocate.xml index 2606f2028b..88ebfb0948 100644 --- a/docs-xml/smbdotconf/tuning/strictallocate.xml +++ b/docs-xml/smbdotconf/tuning/strictallocate.xml @@ -10,14 +10,26 @@ 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. - This can be slow on some systems. + This can be slow on some systems. When you work with large files like + >100MB or so you may even run into problems with clients running into + timeouts. - When strict allocate is no the server does sparse - disk block allocation when a file is extended. + 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 ammounts + 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. + + 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. - Setting this to yes can help Samba return - out of quota messages on systems that are restricting the disk quota - of users. no -- cgit