It is true that they have a particularly robust, distributed backup system that can/has come in handy, but FWIW the timing matters to them. English Wikipedia receives ~2 edits per second, or 172,800 per day. Many of them are surely minor and/or automated, but still: 1,036,800 lost edits is a lot!

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shevy-java 5 hours ago | parent | next [-]

Are they really lost though? I think they should not be lost; they could be stored in a separate database additionally.

	▲	derefr 4 hours ago \| parent [-]
		In fact, as long as the malware is just doing deletes, you can just merge the two "timelines" by restoring the snapshot and then replaying all the edits but ignoring the deletes. Lost deletes really aren't much of a problem!

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Kiboneu 4 hours ago | parent | prev [-]

Filesystem & database snapshots are very cheap to make, you can make them every 15 minutes. You can expire old snapshots (or collapse the deltas between them) depending on the storage requirements.

	▲	squeaky-clean 3 hours ago \| parent [-]
		That doesn't really matter though against an attack that takes some time to spread. If the attack was active for let's say, 6 hours, then 43,000 legitimate edits happened in between the last "clean" snapshot and the discovery of the attack. If you just revert to the last clean snapshot you lose those legitimate edits.