Hi Alvin. I read on your site that you stopped work on a project because LVM snapshots potentially decreased IO performance, and I also saw that you worked on a perl project to make copies of VMs, so therefore I address my question directly to you. Your work reminded me of something I read some weeks ago on qcow2 on <a href="http://people.gnome.org/~markmc/qcow-image-format.html">http://people.gnome.org/~markmc/qcow-image-format.html</a> and which raised my brows at the time: "Snapshots - "real snapshots" - are represented in the original image itself. Each snapshot is a read-only record of the image a past instant. The original image remains writable and as modifications are made to it, a copy of the original data is made for any snapshots referring to it. " I tried to find more info about this, but didn't yet. So here's my question: does anybody know whether, having made snapshots of a VM during several stages of its life (clean install, important service installed, ...), affects IO performance of any writes made after snapshotting, as one could suspect from my quote above? Regards, Jürgen