peak amount of memory occupied by any process with "FOO" in its name

grep VmHWM /proc/$(pgrep -d '/status /proc/' FOO)/status
Show the maximum amount of memory that was needed by a process at any time. My use case: Having a long-running computation job on $BIG_COMPUTER and judging whether it will also run on $SMALL_COMPUTER. VmHWM: Peak resident set size ("high water mark")
Sample Output
user@host:~$ grep VmHWM /proc/$(pgrep -d '/status /proc/' bash)/status
/proc/1614/status:VmHWM:	    9040 kB
/proc/4536/status:VmHWM:	    8940 kB
/proc/6521/status:VmHWM:	    8868 kB
/proc/11742/status:VmHWM:	    8760 kB
/proc/14246/status:VmHWM:	    8624 kB

2014-11-05 15:06:29

What Others Think

That's a very nice bit of /proc to know. However the command is a bit crazy. Also, if the command isn't running the output is junk. First, I tried using sed: grep VmHWM $(pgrep FOO | sed 's!.*!/proc/\0/status!') A bit simpler to follow, but if the command doesn't exist, grep just sits there waiting. What we needed was xargs: pgrep FOO | xargs -rI{} grep -H VmHWM /proc/{}/status xargs -r -- don't run if there are no matches -I{} -- capital i, replace this string {} with the matches grep -H -- force the display of the filename
flatcap · 359 weeks ago

What do you think?

Any thoughts on this command? Does it work on your machine? Can you do the same thing with only 14 characters?

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