Hello everybody, as a long time (decades) Java developer now converting to bare metal C, I would like to ask about how to do parallelization properly. The poor man's approach the Java APIs implement pretty much resemble what every one else is doing. Take the number of processors available in a system and size everything to this. This just does not make sense, because there are a lot of other processes or even kernel threads competing in parallel. Is there some standard API (e.g. POSIX) allowing an application to reserve a certain amount of processors to a specific application? What I mean is - you can run make -j8 on a machine with 16 CPUs. That does not mean that this make really can use those 8 CPUs exclusively as requested. Same for the Java VM. Starts multiple background threads. Needs to share all CPUs with the OS and various other processes. Still just uses the number of CPUs available to size things. I am searching for some kind of system API allowing an application to reserve a certain amount of CPUs exclusively - not shared with any other application - maybe not even the OS. Does this make sense?
-- Christian
