On Thu, 2002-09-26 at 15:32, Eric Sandeen wrote:
> 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.
There has recently been some internal push to make this happen too,
but no decision about doing it, or how to resource doing it.
Probably an extension of the xfs_fsr approach would be the way to
go. One major issue is it is impossible to do this without changing
inode numbers. Some applications rely on inode numbers remaining a
constant.
OK, I know that does not tell you anything, but I have just spent six
hours talking to someone and my brain is fried!
Steve
>
> -Eric
>
> 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).
> >
> > -Mike
> >
> --
> Eric Sandeen XFS for Linux http://oss.sgi.com/projects/xfs
> sandeen@xxxxxxx SGI, Inc. 651-683-3102
>
--
Steve Lord voice: +1-651-683-3511
Principal Engineer, Filesystem Software email: lord@xxxxxxx
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