Help with Linux and performance
Here is the scenario:
Me and a friend have a headless server set up that we access with ssh and scp. The server is an old desktop machine with a Q6600 and 4GB RAM, with Ubuntu server 11.10. We use it as a Minecraft server, which is a _very_ heavy application, that needs to run smooth as silk to be enjoyable for the clients.
Once a day a cron job activates a small program which take a snapshot of our game server and saves it as a PNG. This is also a _very_ heavy process, AFAICT this process uses ray-tracing to generate the image, which is a 13000*13000 PNG file, it takes about half an hour to finish up. So the thing is, the main Minecraft application gets laggy and unresponsive during this period, which is strange since Minecraft is completely single-threaded and only uses a single core when running. If i fire up htop while both processes are running i see one core screaming along at 100% and then 3 other cores doing nothing, shouldn't the operating system be handling this alot better?
These are 2 seperate programs, one is a java application, the other is written in C++, why do they have to fight over the same core?
Also, we need some heavy compression for the PNG files themselves, what compression software should we use? It seems it's either bzip2 or gzip, but which has the highest compression rate, and are there any flags i can pass to them to make them compress even further?
If you haven't noticed im pretty new with Linux, but it's been quite enjoyable so far.