How can I measure the actual memory usage of an application or process?

Question

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How do you measure the memory usage of an application or process in Linux?

From the blog articl

Answer 1

In recent versions of Linux, use the smaps subsystem. For example, for a process with a PID of 1234:

cat /proc/1234/smaps

It will tell you exactly how much memory it is using at that time. More importantly, it will divide the memory into private and shared, so you can tell how much memory your instance of the program is using, without including memory shared between multiple instances of the program.