You nailed it! So, if I understand correctly, the crucial difference is that my original script forked a process for every single file in queue, while yours only for $maxforks, right?

The documentation on fork() says it "does a fork(2) system call to create a new process running the same program at the same point" and "great care has gone into making it extremely efficient (for example, using copy-on-write technology on data pages)", so I assumed an array with a few hundred thousand elements wouldn't pose a problem. Obviously, I was wrong.

I benchmarked the 3 proposed updates from choroba, marioroy (who had also been of great help in my previous question) and kikuchiyo. The tests ran in a loop utilizing 8, 16, 32, etc up to 4096 threads over 3457, 34570 and 345700 files and the results are very interesting and demonstrate the strong and weak points of each implementation. The test box was a mobile 4th-gen, 4c/8t i7 with 32GB of RAM. All tests ran on tmpfs.

I created some graphs for easier interpretation of the results but it appears I can't link to imgur; is there an "allowed" image posting site I can link to?

All said, I'd like to thank every one of you, your insight and wisdom have fully answered my questions.

In reply to Re^2: Script exponentially slower as number of files to process increases by xnous
in thread Script exponentially slower as number of files to process increases by xnous

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