snapshots not stable with 2.3.99pre2

While testing lvm with linux 2.3.99pre2 I had 2 crashes while trying out snapshots. Without snapshots lvm seems to be stable.

Another problem is (probably) a missing check in lvextend: I tried to extend a striped lv, and while I had enough space available, nearly all this space was on one pv, so it was not possible to create a correctly striped volume with the extended size. But I didn't get the error message I expected: lvextend told me everything is ok, but when I tried to ext2resize the filesystem, I got a segmentation fault.

When snapshots were mentioned the other week, I tried finding something in the docs, but I couldn't.
Could someone please give me a reference on what snapshots are and how they work - or is it "RTF..Source" ?-)

cu
Richard
--
Richard Heider jr. http://www.heider.de/

Snapshots are virtual copys of logical volumes. Such a copy is read only and doesn't change when you write to the cloned volume.

This is often used for backups: If you backup a filesystem while it's in use, you may end up with an inconsistant or incomplete backup. (after you wrote the first half of your filesystem to tape, someone moves a file from the second half to the first one, so you miss it when you write the second half to tape, for example.)
If you have snapshots, you create the snapshot at one moment and then write the (read only) snapshot to tape.

Jan