I just tried to implement a programming exercise from my course (Conway’s Game of Life). It works quite well (source), but there’s one problem: It keeps getting killed when it runs here.
Is there some way to program it in such a way that it won’t run afoul of the process killer, or should I just stop using the server to try out Java exercises?
I would suggest running it on your computer (or server, if you have one) at home instead, as ProcWatch kill just about anything and everything that moves these days… 
Are there any criteria for a process that gets targeted - load, amount of memory, number of seconds run? Or is it simply random?
I’m not entirely sure of the criteria myself, as that is apparently rather “secret”, but I do know that if you exceed roughly 50meg of RAM (it may be slightly more) for any given script or application, it’ll get killed pretty fast.
Anything that consumes more than 1 minute of CPU time I believe also gets killed (hence no persistent processes).
You could always try writing into support and ask, but the last time I checked, they don’t give out exact details (and I’m sure for a good reason).
Well, I don’t want to know it for nefarious purposes, I’d just have liked some pointers regarding how to run a program on the server without disrupting it and being a pest to the other users. But thanks for those hints. 
Another trick you can use to help keep your process from getting killed is to use “nice” to tell the system to use a lower cpu priority. It won’t be smooth or pretty but it won’t get killed as quickly.
Wholly - Use promo code WhollyMindless for full 97$ credit. Let me know if you want something else!