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

Beside the solutions listed in the answers, you can use the Linux command "top". It provides a dynamic real-time view of the running system, and it gives the CPU and memory usage for the whole system, along with for every program, in percentage:

top

to filter by a program PID:

top -p 

To filter by a program name:

top | grep 

"top" provides also some fields such as:

VIRT -- Virtual Image (kb): The total amount of virtual memory used by the task

RES -- Resident size (kb): The non-swapped physical memory a task has used ; RES = CODE + DATA.

DATA -- Data+Stack size (kb): The amount of physical memory devoted to other than executable code, also known as the 'data resident set' size or DRS.

SHR -- Shared Mem size (kb): The amount of shared memory used by a task. It simply reflects memory that could be potentially shared with other processes.

Reference here.