Limit physical memory per process

Question

I am writing an algorithm to perform some external memory computations, i.e. where your input data does not fit into main memory and you have to consider the I/O complexity.

Answer 1

I would use the setrlimti with the RLIMIT_AS parameter to set the limit of virtual memory (this is what ulimit does) and then have the process use mlockall(MCL_CURRENT|MCL_FUTURE) to force the kernel to fault in and lock into physical RAM all the process pages, so that amount virtual == amount physical memory for this process