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! <[EMAIL PROTECTED]> | http://jeremy.zawodny.com/ [book] High Performance MySQL -- http://highperformancemysql.com/ -- MySQL General Mailing List For list archives: http://lists.mysql.com/mysql To unsubscribe: http://lists.mysql.com/[EMAIL PROTECTED]
