Bruce Momjian wrote:
> Tom Lane wrote:
>> The we-already-pinned-the-page problem is a bit nasty but may not be
>> insurmountable.
If you find a way, that would be great.
> As I understand it, there are two HOT features:
>
> Single-chain pruning, which trims HOT chains but doesn't reuse
> the space
>
> Defragementation, which prunes the entire page and reuses space
> and handles deleted rows, etc.
I'm repeating myself, but I would split that second operation into two
parts while we think about this: pruning the entire page, and
defragmenting (PageRepairFragmentation). Tom wondered why they're
separated in the patch. As the patch stands, there is no reason, but I
feel that separating them and doing them at different times might be an
important piece in the puzzle.
--
Heikki Linnakangas
EnterpriseDB http://www.enterprisedb.com
