Invoke and track memory usage of one process

I want to run a memory-consuming program and track its memory usage over time. The program ends in a few seconds after invoked.

This previous question suggested sysstat package . While its pidstat utility partly does what I want, it fails to meet my 2 needs:

• It accepts a minimal interval of 1s, but I want to measure at shorter granularity. (0.1s should be fine)
• It only tracks an existing process, while I cannot always be present to copy&paste the pid.

Are there some alternative scripts / utilities to do the invoke-and-measure job better?

This should do what you need. It gets the information from /proc/$PID/statm and prints (from man procfs):

              size       total program size
                         (same as VmSize in /proc/[pid]/status)
              resident   resident set size
                         (same as VmRSS in /proc/[pid]/status)
              share      shared pages (from shared mappings)
              data       data + stack

The script:

#!/usr/bin/env bash 

## Print header
 echo -e "Size\tResid.\tShared\tData\t%"
 while [ 1 ]; do
    ## Get the PID of the process name given as argument 1
     pidno=`pgrep $1`
    ## If the process is running, print the memory usage
     if [ -e /proc/$pidno/statm ]; then
     ## Get the memory info
      m=`awk '{OFS="\t";print $1,$2,$3,$6}' /proc/$pidno/statm`
     ## Get the memory percentage
      perc=`top -bd .10 -p $pidno -n 1  | grep $pidno | gawk '{print \$10}'`
     ## print the results
      echo -e "$m\t$perc";
    ## If the process is not running
     else
      echo "$1 is not running";
     fi
 done

You can then call the script, giving it a process name as input. For example:

$ memusage.sh firefox
Size    Resid.  Shared  Data    %
517193  261902  9546    400715  12.8
517193  261902  9546    400715  12.8
517193  261902  9546    400715  12.8
517193  262100  9546    400715  12.8
517193  262100  9546    400715  12.8
517193  262100  9546    400715  12.8
517209  261899  9546    400731  12.8
517209  261899  9546    400731  12.8

NOTES:

• This assumes that there is only a single running process with the name specified.

After years I found that valgrind (also) have a tool for this:

# record memory usage

$ valgrind --tool=massif bash -c "sleep 5; echo hey";
==5281== Massif, a heap profiler
==5281== Copyright (C) 2003-2015, and GNU GPL'd, by Nicholas Nethercote
==5281== Using Valgrind-3.12.0 and LibVEX; rerun with -h for copyright info
==5281== Command: bash -c sleep\ 5;\ echo\ hey
==5281==
hey
==5281==

# print the usage (5281 was the pid of bash, your filename will be different)
$ ms_print massif.out.4682

Note: valgrind does more than observing: it need to inject some code and take snapshot of memory. This may harm precision of statistics.