From: Jignesh K. Shah <J.K.Shah@Sun.COM>
To: josh@agliodbs.com
Cc: pgsql-performance@postgresql.org
Subject: Re: User concurrency thresholding: where do I look?
Date: Tue, 31 Jul 2007 17:46:26 -0400
Message-ID: <46AFADB2.5070409@sun.com> (raw)
In-Reply-To: <200707311433.20568.josh@agliodbs.com>
References: <200707190828.59088.josh@agliodbs.com>
<46A90F83.8050401@sun.com>
<1185527727.4191.22.camel@ebony.site>
<200707311433.20568.josh@agliodbs.com>
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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To: pgsql-performance@postgresql.org
Cc: J.K.Shah@Sun.COM, josh@agliodbs.com
Subject: Re: User concurrency thresholding: where do I look?
In-Reply-To: <46AFADB2.5070409@sun.com>
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