From: Josh Berkus <josh@agliodbs.com>
To: Alvaro Herrera <alvherre@commandprompt.com>
Cc: pgsql-performance@postgresql.org
Subject: Re: User concurrency thresholding: where do I look?
Date: Thu, 19 Jul 2007 09:22:24 -0700
Message-ID: <200707190922.24497.josh@agliodbs.com> (raw)
In-Reply-To: <20070719154912.GG6538@alvh.no-ip.org>
References: <200707190828.59088.josh@agliodbs.com>
<20070719154912.GG6538@alvh.no-ip.org>
Alvaro,
> Have you messed with max_connections and/or max_locks_per_transaction
> while testing this? The lock table is sized to max_locks_per_xact times
> max_connections, and shared memory hash tables get slower when they are
> full. Of course, the saturation point would depend on the avg number of
> locks acquired per user, which would explain why you are seeing a lower
> number for some users and higher for others (simpler/more complex
> queries).
That's an interesting thought. Let me check lock counts and see if this is
possibly the case.
--
Josh Berkus
PostgreSQL @ Sun
San Francisco
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To: pgsql-performance@postgresql.org
Cc: josh@agliodbs.com, alvherre@commandprompt.com
Subject: Re: User concurrency thresholding: where do I look?
In-Reply-To: <200707190922.24497.josh@agliodbs.com>
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