On Mon, Jun 21, 2004 at 06:57:51PM +0200, Leonardo Francalanci wrote:
> I'm doing some tests on a 16.000.000 rows table.
> Doing a simple "SELECT SUM(MYFIELD) FROM MYTABLE" I noticed
> that disks are at 0.1%, while cpu arrives up to 80%.
> How is that possible? My HDs are IDE. MySql has around
> 30Mb of ram, I thought it should read a lot from disk.
>
> Even doing lots of queries by key I get only high cpu usage,
> not disk reads.
>
> Is that normal?
Hard to say, but in a table scan the CPU does have a lot of work to
do. It needs to do about 16,000,000 comparisons (based on your info).
Jeremy
--
Jeremy D. Zawodny | Perl, Web, MySQL, Linux Magazine, Yahoo!
<Jeremy@stripped> | http://jeremy.zawodny.com/
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