Re: CPU bound

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