speed up php-cli

Question

Why is a php cli process using 25% of CPU, is there a way to reduce this? Right now I'm running 3 instances but obviously I would like to run much more to finish the job faster.

Background info: I'm moving data from a transbase db to mysql db. EDIT: If I run this in a browser there isn't such a noticeable load on the CPU.

Answer 1

More processes doesn't mean faster processing. The PHP process takes as much CPU as it can to finisgh the task as quick as possible. It's probably 25% because you got a quad-core processor and it's a single threaded task.

Ideally, you would need 4 processes if you could assign each of them to a different code. Also, because of waiting for database or disk-I/O, a single thread cannot fully use all CPU power all the time, so go ahead and run more processes. It's not that a 5th processes will crash because all CPU power is used up; it will just take its share, while the OS divides processing power to all running processes.

Just dont' start too many; every process has a little overhead, and you won't benefit from having 200 simultaneous processes.