Tom Lane wrote:
> Sorry, I got a bit confused there. The vacuum's intentional pruning
> will use its own OldestXmin variable, which is known current at the
> start of the vacuum (and I think there were even proposals to advance
> it more frequently than that). However, a vacuum could require some
> incidental system catalog fetches, which I think could result in
> prune operations based on RecentGlobalXmin on the catalog pages
> (cf index_getnext).
Hmm, right, and what Heikki said too.
> Anyway I think we are on the same page about the rest of the issues.
> Did you want to work on fixing them, or shall I?
Is this more or less what you had in mind?
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