Online resizing of ext3 filesystems {shrink}

[Chris Adams]

Once upon a time, goemon at anime.net <goemon at anime.net> said:
> On Sun, 8 Jan 2006, Bill Rugolsky Jr. wrote:
> >Shrinking, on the other hand, presents a host of problems, including
> >the need to compact the data below the new boundary, and deal with
> >current users of the filesystem that may, e.g., have a region of
> >some file memory-mapped, or may have I/O in flight.
> 
> what about if you're shrinking the filesystem to a point where nothing 
> is/has ever been used/mapped and where no data needs to be compacted?

Without shrink, expand is not all that useful.  With LVM, shrink and
expand can be used to re-allocate free space to different filesystems.
Without shrink, that can't be done.

> >But nobody ever bothered to write the userland code for an online 
> >defragmenter.
> 
> This is a major advantage microsoft has with NTFS over linux :-(

I don't know about NTFS, but ext2/3 is generally pretty resistant to
significant fragmentation (fragmentation that would cause a performance
impact), so online defrag isn't that big of a deal.
-- 
Chris Adams <cmadams at hiwaay.net>
Systems and Network Administrator - HiWAAY Internet Services
I don't speak for anybody but myself - that's enough trouble.