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

Three more methods to try:

1. ps aux --sort pmem
   It sorts the output by %MEM.
2. ps aux | awk '{print $2, $4, $11}' | sort -k2r | head -n 15
   It sorts using pipes.
3. top -a
   It starts top sorting by %MEM

(Extracted from here)