Re: In progress INSERT wrecks plans on table - Mailing list pgsql-performance

From Mark Kirkwood
Subject Re: In progress INSERT wrecks plans on table
Date
Msg-id 51870CB6.6090404@catalyst.net.nz
Whole thread Raw
In response to Re: In progress INSERT wrecks plans on table  (Simon Riggs <simon@2ndQuadrant.com>)
Responses Re: In progress INSERT wrecks plans on table
Re: In progress INSERT wrecks plans on table
List pgsql-performance
On 05/05/13 00:49, Simon Riggs wrote:
> On 3 May 2013 13:41, Simon Riggs <simon@2ndquadrant.com> 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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