From: Joshua D. Drake <jd@commandprompt.com>
To: gvfontenay@lbl.gov
Cc: pgsql-performance@postgresql.org
Subject: Re: Strange explain on partitioned tables
Date: Fri, 23 Jul 2010 15:16:10 -0700
Message-ID: <1279923370.9866.37.camel@jd-desktop.unknown.charter.com> (raw)
In-Reply-To: <4C4A11CB.6040800@lbl.gov>
References: <4C47F8C8.10005@edd.fr>
<4C484874.3060609@2ndquadrant.com>
<4C4A11CB.6040800@lbl.gov>
On Fri, 2010-07-23 at 15:03 -0700, Gerald Fontenay wrote:
> > The PostgreSQL partitioning system is aimed to support perhaps a
> > hundred inherited tables. You can expect to get poor performance on
> > queries if you create 1000 of them.
>
> Hi,
>
> Why is that you would expect poor performance for say 1000 or more? I
> have a ~1000 inherited tables and I don't see any significant slowdowns.
> I only ever access a single inherited table at a time though in this
> situation. I suppose I am using inheritance only for organization in
> this case...
It is variable based on workload and as I recall has to do with the
planning time. As the number of children increases, so does the planning
time.
Joshua D. Drake
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To: pgsql-performance@postgresql.org
Cc: jd@commandprompt.com, gvfontenay@lbl.gov
Subject: Re: Strange explain on partitioned tables
In-Reply-To: <1279923370.9866.37.camel@jd-desktop.unknown.charter.com>
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