From: Mark Kirkwood <markir@paradise.net.nz>
To: Kurt Overberg <kurt@hotdogrecords.com>
Cc: pgsql-performance@postgresql.org
Subject: Re: Weird 8.2.4 performance
Date: Fri, 08 Jun 2007 11:04:54 +1200
Message-ID: <46688F16.90207@paradise.net.nz> (raw)
In-Reply-To: <C040B179-DBCF-441F-9677-E03AE663CEF9@hotdogrecords.com>
References: <371D1936-E96B-4865-AEEF-C82AC41C2982@hotdogrecords.com>
<46674AEF.6040803@paradise.net.nz>
<4667CE87.30101@archonet.com>
<C040B179-DBCF-441F-9677-E03AE663CEF9@hotdogrecords.com>
Kurt Overberg wrote:
> work_mem = 100MB # when I ran the original query,
> this was set to 1MB, increased on Mark Kirkwood's advice, seemed to help
> a bit but not really
>
For future reference, be careful with this parameter, as *every*
connection will use this much memory for each sort or hash (i.e it's not
shared and can be allocated several times by each connection!)...yeah, I
know I suggested increasing it to see what effect it would have :-).
And I'd agree with Steiner and others, looks like caching effects are
the cause of the timing difference between production and the mac!
Cheers
Mark
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To: pgsql-performance@postgresql.org
Cc: markir@paradise.net.nz, kurt@hotdogrecords.com
Subject: Re: Weird 8.2.4 performance
In-Reply-To: <46688F16.90207@paradise.net.nz>
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