On Thu, Oct 16, 2003 at 12:49:41PM -0400, [EMAIL PROTECTED] wrote: > In a message dated 10/16/03 9:27:04 AM Eastern Daylight Time, > [EMAIL PROTECTED] writes: > > > This is down to the OS. As MySQL is multy threaded its all down to SMP > > support. > > > > with all due respect, I don't think that is 100% true. Although > certainly the underlying OS kernel must support multi-processors and > discrete processor selection functionality, I am looking for > user-based control of query execution. That would have to come from > the DB package. Oracle has such functionality (at least on > Unix-based versions) that I've used recently, including the ability > to dynamically allocate more processors to a running query. We do > this all the time to complete a task of higher priority than others. > Certainly with Oracle one pays dearly for such software. I am just > wondering what options are available in MySQL (if any).
MySQL offers no control over how many processors a giver query will use because each query can use only a single processor at a time. There's a 1-to-1 mapping from queries to threads in MySQL. Each thread may execute on only one CPU. Jeremy -- Jeremy D. Zawodny | Perl, Web, MySQL, Linux Magazine, Yahoo! <[EMAIL PROTECTED]> | http://jeremy.zawodny.com/ MySQL 4.0.15-Yahoo-SMP: up 32 days, processed 1,221,267,552 queries (431/sec. avg) -- MySQL General Mailing List For list archives: http://lists.mysql.com/mysql To unsubscribe: http://lists.mysql.com/[EMAIL PROTECTED]
