On Wed, 8 Feb 2012 17:19:05 -0800, Ori Bani <orib...@gmail.com> wrote: > Hi, > > I'd like to know if anyone here has any thoughts or opinions about the > best linux filesystem to use for an email system. There will be some > small amount of website data on the system (including webmail to read > the emails), although I could move that to another partition if need > be. > > Anyone use ext4? Btrfs? Something else? Is ext3 fine even in high > volume email servers? Anyone use any non-default values for block size > or journaling type? > > Thank you
Ori, We are currently testing XFS 3.1.1 on Centos 6.2. We got the knack for XFS after watching this video where an XFS dev speaks to the new features and other interesting aspects of filesystem development: http://www.youtube.com/watch?feature=player_embedded&v=FegjLbCnoBw Namely the way they reduce metadata bandwidth was a huge improvement for me. In our environment we have 2.5 TB of maildir structured files, and moving it to XFS (from ext3) has been like night and day. We had a script that created all the user's home directories on the new filesystem in this format '/mail/a/n/andy/Maildir/blah', for 65000 user accounts. It completed in about five minutes, which ext3 had taken upwards of two hours to do in the past. Big difference. We then started moving the mail over to the new file system using 4 parallel rsyncs it took about 2 hours to move the mail to the new file system, which was fairly quick. So far everything seems a bit snappier when loading mail into a client, or into webmail. The mail servers are running low load average, and the IOPS have decreased by about a fifth from the ext3. Now if you're looking at doing something a bit more extravagent you should look at GlusterFS, a distributed file system that can write synchronously mirrored copies of files to multiple storage nodes, and exports it's file system using NFS as well as an improved client provided by Gluster that has better file locking. You can use XFS/EXT4/BTRFS/etc. underneath GlusterFS as your core storage, and the GlusterFS runs on top of the multiple nodes, distributing files over the cluster making a highly performant and highly avialiable storage backend. We have done quite a bit of testing with this, and there are certainly some gotchas to be aware of when storage nodes fail, but it's well documented. Overall it's a great tool if you are looking at doing high demand file serving and could benefit from a clustered file system.
