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From: Alvaro Herrera <alvherre@commandprompt.com>
To: Jignesh K. Shah <J.K.Shah@Sun.COM>
Cc: Simon Riggs <simon@2ndquadrant.com>
Cc: Tom Lane <tgl@sss.pgh.pa.us>
Cc: Josh Berkus <josh@agliodbs.com>
Cc: pgsql-performance@postgresql.org
Subject: Re: User concurrency thresholding: where do I look?
Date: Fri, 27 Jul 2007 04:58:05 -0400
Message-ID: <20070727085805.GF2550@alvh.no-ip.org> (raw)
In-Reply-To: <46A90F83.8050401@sun.com>
References: <1545.1185214760@sss.pgh.pa.us>
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	<13162.1185405865@sss.pgh.pa.us>
	<46A8AFDF.3050804@sun.com>
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	<46A8F9AA.4040507@sun.com>
	<1185480291.5510.22.camel@ebony.site>
	<46A90F83.8050401@sun.com>

Jignesh K. Shah wrote:

> Top Wait time   seems to come from the following code path for 
> ProcArrayLock:
>
>             Lock Id            Mode           Count
>       ProcArrayLock       Exclusive              21
>
>             Lock Id   Combined Time (ns)
>       ProcArrayLock           5255937500
>
>             Lock Id   Combined Time (ns)
>
>
>              postgres`LWLockAcquire+0x1f0
>              postgres`CommitTransaction+0x104

Yeah, ProcArrayLock is pretty contended.  I think it would be kinda neat
if we could split it up in partitions.  This lock is quite particular
though.

-- 
Alvaro Herrera                                http://www.CommandPrompt.com/
PostgreSQL Replication, Consulting, Custom Development, 24x7 support

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  Subject: Re: User concurrency thresholding: where do I look?
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