This is just a random idea that popped through my mind while I was looking into hardening a filesystem against damage, might be impractical, but the idea seems promising, and well suited to a snapshot file system.

I'm sure some creative shell scripting could do something like this already, but I was more looking for something more bulletproof.

General idea would be to have a transient snapshot (optional quota support possibility here) on top of a base snapshot (possibly readonly). On system start/restart (whether clean or dirty), the transient snapshot would be flushed, and the system would restart the snapshot, basically restarting from the base snapshot. If desired, the transient snapshot could be promoted to a regular snapshot (say after a software upgrade). If desired, a different base snapshot could be selected (although I'm sure the file system would have to be restarted to do this)

From a caching perspective, this could make a noticable performance difference, since if you're running in a transient snapshot, the file system can be _extremely_ lazy about committing changes to disk.

For the optional quote support I mentioned, on an unattended box, if the quota gets exceeded, a system reboot would probably fully correct the system. (Presumably a log file got out of control in that situation).
--
To unsubscribe from this list: send the line "unsubscribe linux-btrfs" in
the body of a message to majord...@vger.kernel.org
More majordomo info at  http://vger.kernel.org/majordomo-info.html

Reply via email to