From: Kenneth Marshall <ktm@rice.edu>
To: Mark Makarowsky <bedrockconstruction@yahoo.com>
Cc: pgsql-performance@postgresql.org
Subject: Re: Update table performance
Date: Tue, 7 Aug 2007 08:15:37 -0500
Message-ID: <20070807131537.GE12924@it.is.rice.edu> (raw)
In-Reply-To: <435532.80672.qm@web32210.mail.mud.yahoo.com>
References: <435532.80672.qm@web32210.mail.mud.yahoo.com>
Mark,
You are not alone in the fact that when you post your system
specifications, CPU and memory are always listed while the
disk I/O subsystem invariably is not. This is a very disk
intensive operation and I suspect that your disk system is
maxed-out. If you want it faster, you will need more I/O
capacity.
Regards,
Ken
On Tue, Aug 07, 2007 at 05:58:35AM -0700, Mark Makarowsky wrote:
> I have a table with 4,889,820 records in it. The
> table also has 47 fields. I'm having problems with
> update performance. Just as a test, I issued the
> following update:
>
> update valley set test='this is a test'
>
> This took 905641 ms. Isn't that kind of slow? There
> aren't any indexes, triggers, constraints or anything
> on this table. The version of Postgres is "PostgreSQL
> 8.2.4 on i686-pc-mingw32, compiled by GCC gcc.exe
> (GCC) 3.4.2 (mingw-special)". The operating
> environment is Windows 2003 Standard Edition w/service
> pack 2. It is 2.20 Ghz with 1.0 GB of RAM. Here is
> the results from Explain:
>
> "Seq Scan on valley (cost=0.00..1034083.57
> rows=4897257 width=601)"
>
> Here are the settings in the postgresql.conf. Any
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To: pgsql-performance@postgresql.org
Cc: ktm@rice.edu, bedrockconstruction@yahoo.com
Subject: Re: Update table performance
In-Reply-To: <20070807131537.GE12924@it.is.rice.edu>
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