This is similar to my earlier question but more generic. I have a system with 16GB of memory, 16 cores, supposedly quality hard drives, RHEL 5, MySQL 5.0.x. Yes, I know, we're working on upgrading that. But this is what we have.
I just ran a few queries with large inserts and complicated joins that caused load to spike to 6, from where it usually is at 1.10. People started reporting that the website was becoming sluggish. These are all MyISAM table, but this is not about row vs table locking - the performance loss was on an entirely separate set of tables from what was being operated on. This is not about 'can't execute other queries', this is about 'everything else on the system slows down'.
I've been trying to google this and can find no other resource saying a query is supposed to spike server load like that. So I'm starting to wonder: Is it just me? If so, do you have any suggestions? And if not, do you have any mitigation suggestions?