Hannu Krosing wrote:
> I guess we can't easily start locking some subarea of a page, say 256
> byte subpage, or just the tuple.
> OTOH it may be possible as we don't need to lock page header for
> sequences as the tuple is updated in place and will not change in size.
Huh, we _can_ lock individual tuples, using LockTuple() (or rather,
heap_lock_tuple). Since the tuple is modified in place, there's no need
to lock the whole page.
> OTOOH, I'm afraid we still need to WAL the whole page, so the savings
> will be marginal.
Huh, why? We can just keep the current WAL logging for sequences, or
something very similar, can't we?
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Alvaro Herrera http://www.CommandPrompt.com/
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