How to view total CPU and memory usage of per system user in Linux

Question

I know the top command to see the process of CPU and memory usage, but some users of the system can generate a lot of processes, if I wanna know total CPU and memory usage of an user,I must count it by my own,so,is there a command which can view total CPU and memory usage of per system user in Linux，and order by system username?

Answer 1

I don't think there's a direct way of doing it - but one way would be to parse the output of top. The following

top -b -n 1 -u username | awk 'NR>7 { sum += $9; } END { print sum; }' 

does just that. For each process in top (for a given user) awk will strip the 9th delimited field (i.e. CPU %) 7 lines down (i.e. start of the top table) for each line, then sum them. Saves you fiddling about at least!

A couple of discussions around this...

Howtoforge, Stackexchange

Answer 2

Complementing @hygris command, we can add the following and have the information for all the users at the same time:

top -b -n 1  |\
 awk ' BEGIN{OFS="\t"} 
 NR>7{ sum[$2] += $9; t += $9;} 
END {print "user","%CPU" ; for (u in sum){print u,sum[u]}print "total",t}'

The above command will print the total at the end.

If you want to add the memory:

 top -b -n 1  |\
  awk ' BEGIN{OFS="\t"} 
     NR>7 { sum[$2] += $9; t += $9; mem[$2] += $10; tm += $10} 
     END {print "user","%CPU","%MEM" ; for (u in sum){
         print u"\t"sum[u]"\t"mem[u];} print "total",t,tm}' 

Then, of course, you can pipe and sort the output if that is your goal.