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Cool feature, how far back can I go? Looks like it depends on the setting of the garbage collection interval with a default of 24 hours, how high can I reasonably set that? Is there any overhead besides disk space? Would be nice to have at least a week, so if I delete something on Friday evening, I can still recover it the following week

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[engineer at cockroach]

How high you can set it depends on your access patterns -- there is some overhead to iterating though MVCC revisions during reads, in addition to the on-disk space you mention.

If your workload involves frequent writes to the same rows, GCing some of those revisions sooner would have a greater impact, whereas if you have a write-light workload, or if your writes are spread over rows such that a given row doesn't doesn't see frequent repeated updates, then you could probably use much a higher GC threshold with minimal overhead.

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