The ps command, short for “process status,” has some features for keeping tabs on your program’s memory use. Here is one use of ps:
ps auxw | grep something-interesting
where something-interesting is the PID or program name of interest. So, something like
ps auxw | grep Finder
will show some information about the Finder process:
markd 229 0.0 1.9 2912584 33136 ?? S 0:43.11 /System/ \ Library/CoreServices/Finder.app/Contents/MacOS/Finder -psn_0_2621
In order, the columns are:
Owner of the process (markd).
Process ID ...