tracking memory usage

[John Cremona]

I'm sure I have seen posts about this but cannot find them or guess the appropriate commands.

In testing variants of some new and algorithms to compute the same thing I know how to measure the CPU time taken using cputime(), but is there a way I can tell how much memory was used -- the maximum between two points of the program?

Also with cputime() is time spent in calls to pari library functions (not GP) included?

John