From: Joshua D. Drake <jd@commandprompt.com>
To: Mark Kirkwood <markir@paradise.net.nz>
Cc: Kurt Overberg <kurt@hotdogrecords.com>
Cc: pgsql-performance@postgresql.org
Subject: Re: Weird 8.2.4 performance
Date: Thu, 07 Jun 2007 16:09:34 -0700
Message-ID: <4668902E.4040909@commandprompt.com> (raw)
In-Reply-To: <46688F16.90207@paradise.net.nz>
References: <371D1936-E96B-4865-AEEF-C82AC41C2982@hotdogrecords.com>
<46674AEF.6040803@paradise.net.nz>
<4667CE87.30101@archonet.com>
<C040B179-DBCF-441F-9677-E03AE663CEF9@hotdogrecords.com>
<46688F16.90207@paradise.net.nz>
Mark Kirkwood wrote:
> 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 :-).
This is however a parameter that can be set on the fly for the specific
query.
Joshua D. Drake
>
> 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: jd@commandprompt.com, markir@paradise.net.nz, kurt@hotdogrecords.com
Subject: Re: Weird 8.2.4 performance
In-Reply-To: <4668902E.4040909@commandprompt.com>
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