This has been discussed on the list before, and I -think- Steve detailed
the technical difficulties. If you can't find it in the archives, I'll
post a summary.
On Thu, 2002-09-26 at 15:28, Michael Best wrote:
> I know that XFS doesn't/didn't support filesystem resizing that involves
> making the filesystem smaller.
> What are the technical hurdles faced if such a program were to be written?
> Or would this be fairly obvious from reading the filesystem specification?
> Just working from assumptions (perhaps wrong) would be that you would
> have to find all files/inodes that are contained in the space that you
> need to want to truncate from your filesystem. Do some something
> similar to defragment/move those file into the non-truncated space. And
> then rewrite the XFS "superblock"?
> Is the biggest challenge then finding the files that are in this space?
> Telling the filesystem it is smaller? Moving/defragmenting the files?
> Due to limitations on how the code chooses where to write it's next
> blocks? Having to sort all the files on the filesystem?
> Just some random thoughts that came to me about resizing. This would be
> a good thing for LVM if I remember, and I was more or less curious why
> there isn't a tool (and then assumed that there wasn't one because it
> was hard to do due to a design decision).
Eric Sandeen XFS for Linux http://oss.sgi.com/projects/xfs
sandeen@xxxxxxx SGI, Inc. 651-683-3102