To see all the process run by a perticular user
#ps -u username u

-u used to specify user name, and u at the end of the command shows you complete path of the command executed.
#ps -u rajesh u


To see all the files opened by user
#lsof | grep username

#lsof | grep rajesh

To see memory used by a perticular user
#ps -u username u | awk ‘{print $2}’

ps -u krishna u | awk ‘{print $2}’

Now you will get all the PID’s run by user Krishna. So try to get memory usage by using pmap command.

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