Re: In progress INSERT wrecks plans on table

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On 05/05/13 00:49, Simon Riggs wrote:
On 3 May 2013 13:41, Simon Riggs <simon@xxxxxxxxxxxxxxx> wrote:

(3) to make the check on TransactionIdIsInProgress() into a heuristic,
since we don't *need* to check that, so if we keep checking the same
xid repeatedly we can reduce the number of checks or avoid xids that
seem to be long running. That's slightly more coding than my quick
hack here but seems worth it.

I think we need both (1) and (3) but the attached patch does just (1).

This is a similar optimisation to the one I introduced for
TransactionIdIsKnownCompleted(), except this applies to repeated
checking of as yet-incomplete xids, and to bulk concurrent
transactions.

ISTM we can improve performance of TransactionIdIsInProgress() by
caching the procno of our last xid.

Mark, could you retest with both these patches? Thanks.


Thanks Simon, will do and report back.




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