From: Josh Berkus <josh@agliodbs.com>
To: Royce Ausburn <royce@inomial.com>
Cc: pgsql-performance@postgresql.org
Subject: Re: CPU bound
Date: Mon, 13 Dec 2010 10:59:26 -0800
Message-ID: <4D066D0E.6070405@agliodbs.com> (raw)
In-Reply-To: <F13DEE85-D114-4761-AD4D-924F1A741ACC@inomial.com>
References: <F13DEE85-D114-4761-AD4D-924F1A741ACC@inomial.com>
On 12/12/10 6:43 PM, Royce Ausburn wrote:
> Hi all,
>
> I notice that when restoring a DB on a laptop with an SDD, typically postgres is maxing out a CPU - even during a COPY. I wonder, what is postgres usually doing with the CPU? I would have thought the disk would usually be the bottleneck in the DB, but occasionally it's not. We're embarking on a new DB server project and it'd be helpful to understand where the CPU is likely to be the bottleneck.
That's pretty normal; as soon as you get decent disk, especially
something like an SSD with a RAM cache, you become CPU-bound. COPY does
a LOT of parsing and data manipulation. Index building, of course, is
almost pure CPU if you have a decent amount of RAM available.
If you're restoring from a pg_dump file, and have several cores
available, I suggest using parallel pg_restore.
--
-- Josh Berkus
PostgreSQL Experts Inc.
http://www.pgexperts.com
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To: pgsql-performance@postgresql.org
Cc: josh@agliodbs.com, royce@inomial.com
Subject: Re: CPU bound
In-Reply-To: <4D066D0E.6070405@agliodbs.com>
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