How can I set the max number of MySQL processes or threads?

Question

ps axuw| grep mysql indicates only MySQL process, but if I run htop I can see 10 rows each one of them with a separate PID. So I wonder if they are threads or processes that for some reason I cannot see using ps.

Would it make any sense to try to limit them to two on my development machine, where I don't need concurrent access of many clients.

BTW Running on Ubuntu 8.10

Answer 1

You can set the max number of threads in your my.ini like this:

max_connections=2 

However you might also want to set this:

thread_cache_size=1 

The thread cache controls how many it keeps open even when nothing is happening.

Answer 2

MySQL does use threads, ps can see them if you run ps -eLf.

That said, I wouldn't worry about it - dormant threads use almost no resources whatsoever, and if you constrain the server too much it's bound to come back and bite you on the backside sometime later when you've forgotten that you did it.