which file system?

which file system?

[Sebastian Kuzminsky]

I'm building a disk server for a small company.  I'm using the standard
"RAID-array-as-PV" setup, and planning to grow the filesystem as needs
demand.  I'd like to use a filesystem that supports online grow and
online shrink.

XFS, JFS, and Reiser3 all support unlimited online grow but no shrink
at all.

Looks like Ext3 supports online grow, but only up to +16 GB, which
makes it useless on modern disks, much less arrays of modern disks....
Looks like offline grow & shrink are unlimited, which is good.  Lots of
old (unmaintained?) tools and kernel patches here, but lots of recent
activity too.  What's the current status?


-- 
Sebastian Kuzminsky

Re: which file system?

[Andreas Dilger]

On Jan 30, 2006  13:34 -0700, Sebastian Kuzminsky wrote:
> I'm building a disk server for a small company.  I'm using the standard
> "RAID-array-as-PV" setup, and planning to grow the filesystem as needs
> demand.  I'd like to use a filesystem that supports online grow and
> online shrink.
> 
> XFS, JFS, and Reiser3 all support unlimited online grow but no shrink
> at all.
> 
> Looks like Ext3 supports online grow, but only up to +16 GB, which
> makes it useless on modern disks, much less arrays of modern disks....

Actually, ext3 by default with newer e2fsprogs will allow growth up
to 1024x original filesystem size.  The ext2online tool is included
with RHEL4/FC3 e2fsprogs.  The +16GB limit is if you are resizing a
filesystem which has not been "prepared" for online resizing.

Cheers, Andreas
--
Andreas Dilger
Principal Software Engineer
Cluster File Systems, Inc.