From: Jim Vanns <james.vanns@framestore.com>
To: Martin French <Martin.French@romaxtech.com>
Cc: Jim Vanns <james.vanns@framestore.com>
Cc: pgsql-performance@postgresql.org
Cc: pgsql-performance-owner@postgresql.org
Subject: Re: Odd blocking (or massively latent) issue - even with EXPLAIN
Date: Tue, 24 Jul 2012 10:34:11 +0100
Message-ID: <1343122451.12579.155.camel@sys367.ldn.framestore.com> (raw)
In-Reply-To: <OFD096C18F.C98A054A-ON80257A45.0032E783-80257A45.00332C2A@LocalDomain>
References: <1343032905.12579.3.camel@sys367.ldn.framestore.com>
<OF4731D4BD.B722B5CE-ON80257A44.004B3A30-80257A44.004BABD3@LocalDomain>
<1343054763.12579.110.camel@sys367.ldn.framestore.com>
<OF7755750C.7073A920-ON80257A45.00249D8E-80257A45.00259C8D@LocalDomain>
<1343119691.12579.151.camel@sys367.ldn.framestore.com>
<OFD096C18F.C98A054A-ON80257A45.0032E783-80257A45.00332C2A@LocalDomain>
> > That latter test - won't that pretty much just read from the page
> cache?
> > 'sync' may well have forced dirty pages to disk but does it actually
> > evict them to?
>
> Basically, the cache is avoided because of the size of the file.
> 6000000 blocks at 8k exceeds the size of RAM in the machine, so it
> *should* miss the cache and hit the disk directly. :)
Doh!
> >
> > Anyway, that is off topic... perhaps ;)
> >
> > Thanks again,
> >
> > Jim
> >
>
> Cheers
>
> Martin ============================================= Romax Technology
> Limited Rutherford House Nottingham Science & Technology Park
> Nottingham, NG7 2PZ England Telephone numbers: +44 (0)115 951 88 00
> (main) For other office locations see:
> http://www.romaxtech.com/Contact =================================
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--
Jim Vanns
Systems Programmer
Framestore
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To: pgsql-performance@postgresql.org
Cc: james.vanns@framestore.com, Martin.French@romaxtech.com, pgsql-performance-owner@postgresql.org
Subject: Re: Odd blocking (or massively latent) issue - even with EXPLAIN
In-Reply-To: <1343122451.12579.155.camel@sys367.ldn.framestore.com>
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