Hi! I've been trying to find an option to display the exact ram usage value of the user that has the highest. Top command only displays the whole process but I need a "per user" value. Please help

Install smem and do a smem -u.

Or this: (echo "user rss(KiB) vmem(KiB)";
for user in $(users | tr ' ' '\n' | sort -u); do
echo $user $(ps -U $user --no-headers -o rss,vsz \
| awk '{rss+=$1; vmem+=$2} END{print rss" "vmem}')
done | sort -k3
) | column -t

Do I type those directly in unix?

---------- Post added 05-15-14 at 11:49 PM ----------

Do I type these directly on Unix?

Into a terminal.

It does not work.

How will I see the RAM usage of other users also?

This script is using an empty variable (users) which will need to be populated before the script is run for it to work:
users=`ps -eouser --sort user --noheader|uniq`
Or subsititue the command string in place of the $users entry.

An alternative string using less commands with less elegant output could be:
ps -eouser,size --sort user --no-header|awk '!($1 in a){a[$1];print rec,sum;sum=""}{sum+=$2;rec=$1} END {print rec,sum}'

The values are in KB. and represent the currently allocated and intented to be allocated memory not the virtual memory.
However This is still not ideal as it will only provide a rough value.

Cheers

Unix or Linux?

You want to sort on the RES field (resident memory used), or the VIRT (total memory used by teh process - being swap + the in memory resident pages. (use the < and > characters to move the sort column left or right).