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From: Liam Helmer <lists@strongboxlinux.com>
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Date: Thu, 14 Oct 2004 11:18:41 -0700
Message-Id: <1097777922.15920.77.camel@vdesktop.fast1.strongboxlinux.com>
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Subject: [linux-lvm] Snapshot Support
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To: LVM general discussion and development <linux-lvm@redhat.com>

I'm seeing a lot of messages about snapshots sort of working... I should
relay my experience here.

I did some testing with Snapshots in 2.6.8.1, and came up with variable
results. Here's some stuff I found:

reiserfs works badly with read/write snapshots: writing to both the main
filesystem and the snapshot hangs the filesystems permanently (even
after writing stops), and stops LVM from being able to assign more
snapshots/space/etc until a full reboot.

ext3 works OK, albeheit with a definite CPU hit. I tried low-level loads
and it didn't crash, which was certainly better than with reiserfs.

I didn't try a whole lot of other filesystems though. Generally, it
didn't seem quite stable enough, so I decided to wait a few iterations
before working with it seriously. Does anyone know the status of work in
this area? Or if there's some more patches waiting in -mm?

Cheers,
Liam

-- 

StrongBox Linux
http://www.strongboxlinux.com
"Making Security Friendly"