From: Royce Ausburn <royce@inomial.com>
To: Josh Berkus <josh@agliodbs.com>
To: Craig Ringer <craig@postnewspapers.com.au>
Cc: pgsql-performance@postgresql.org
Subject: Re: CPU bound
Date: Tue, 14 Dec 2010 08:03:54 +1100
Message-ID: <7F2CF023-C154-4F7F-9373-2470D4553096@inomial.com> (raw)
In-Reply-To: <4D066D0E.6070405@agliodbs.com>
References: <F13DEE85-D114-4761-AD4D-924F1A741ACC@inomial.com>
<4D066D0E.6070405@agliodbs.com>
Thanks guys - interesting.
On 14/12/2010, at 5:59 AM, Josh Berkus wrote:
> 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: royce@inomial.com, josh@agliodbs.com, craig@postnewspapers.com.au
Subject: Re: CPU bound
In-Reply-To: <7F2CF023-C154-4F7F-9373-2470D4553096@inomial.com>
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