Re: User concurrency thresholding: where do I look? - Mailing list pgsql-performance

From Jignesh K. Shah
Subject Re: User concurrency thresholding: where do I look?
Date
Msg-id 46AFADB2.5070409@sun.com
Whole thread Raw
In response to Re: User concurrency thresholding: where do I look?  (Josh Berkus <josh@agliodbs.com>)
List pgsql-performance
Yep quite a bit of transactions .. But the piece that's slow is where it
is clearing it up in CommitTransaction().
I am not sure of how ProcArrayLock is designed to work and hence not
clear what  we are seeing is what we expect.

Do we have some design doc on ProcArrayLock to understand its purpose?

Thanks.
Regards,
Jignesh


Josh Berkus wrote:
> Simon,
>
>
>> Well thats pretty weird. That code path clearly only happens once per
>> transaction and ought to be fast. The other code paths that take
>> ProcArrayLock like TransactionIdIsInProgress() and GetSnapshotData()
>> ought to spend more time holding the lock. Presumably you are running
>> with a fair number of SERIALIZABLE transactions?
>>
>
> Given that this is TPCC-analog, I'd assume that we are.
>
> Jignesh?
>
>

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