determine total memory used by some user/process

optimuz · 08-12-2009, 01:04 PM

HI guys,

I am pretty new to linux,i would like to know how can i determine
the total/approx memory used by a single user. Example Top output is below

===========================================================================
top - 20:00:50 up 24 days, 2:48, 2 users, load average: 0.43, 0.40, 0.37
Tasks: 172 total, 2 running, 170 sleeping, 0 stopped, 0 zombie
Cpu(s): 4.3% us, 0.7% sy, 0.0% ni, 95.0% id, 0.0% wa, 0.0% hi, 0.0% si
Mem: 24954784k total, 23561312k used, 1393472k free, 318788k buffers
Swap: 2031608k total, 4k used, 2031604k free, 21011868k cached

PID USER PR NI VIRT RES SHR S %CPU %MEM TIME+ COMMAND
7172 rtx 16 0 73696 34m 3352 R 10 0.1 247:50.05 mysqld
5189 rtx 16 0 322m 316m 4268 S 3 1.3 60:50.34 some.f
5193 rtx 16 0 327m 321m 4264 S 2 1.3 60:14.19 some.f
16015 rtx 15 0 73696 34m 3352 S 1 0.1 139:45.09 mysqld
===========================================================================

From the Top output above i found that the memory usage is about 94%. There are about 45 processes owned by "rtx" user.Am wondering if there is any method i can use to determine the total/approx memory used by "rtx" user only...kindly advise..thanks alot

MensaWater · 08-12-2009, 01:57 PM

Linux provides you a wealth of information under /proc including information about each process under /proc/<PID>, where PID is the process ID of the process you're interested in.

Type "man proc". It has lots of detail on one is available including the memory information you want.

fpmurphy · 08-12-2009, 02:04 PM

One way is to write a shell script which implements the following

Code:

ps -ef | grep username
# then call top with the PIDs as parameter
top p pid1 p pid2 > file
# then parse the output with awk or perl

optimuz · 08-12-2009, 02:11 PM

Thanks alot jlightner & fpmurphy. i have found out the total 'rtx' process using #ps -ef | grep -i rtx | grep -v grep | wc -l.
I get a total of 45 processes running now.i can use the 'pmap' command to find the invidual PID memory usage...but am wondering how to find the accumulative memory usage by 'rtx'.I don't know how to parse using awk or perl

optimuz · 08-12-2009, 02:48 PM

Dear jlightner & fpmurphy,

After some RnD over google...i finally found the awk commands to get the total mem usage by a user/pid.

#ps aux | grep --exclude=grep rtx | grep -v grep | awk 'BEGIN{s=0;} {s=s+$6;}END{print s;}' // for total memory

#ps aux | grep –exclude=grep rtx |grep –v grep | awk ‘BEGIN{s=0;} {s=s+$6;} END {print s/45;}’ // for average memory

Thanks alot for the support given !
Have a great day

MensaWater · 08-13-2009, 07:23 AM

One thing to be careful of: Linux unlike other *nix systems tends to show threads win the process list. Since every thread shares the same memory space with the other threads including the main process adding up memory becomes problematic because you're actually adding the same memory space multiple times. You need to either exclude threads in your ps output or be sure you're identifying which ones are using the same memory map.

optimuz · 08-13-2009, 07:30 AM

got that jlightner...thanks