Find out the resource(cpu, memory) usages of users
In some high load situations, we need to find out the resource consumption of each user in the server to figure out the exact issue. There are a lot of options/commands to find the same. Normally, we are using the “ps” and “top” command for performing this. Separating or sorting Unix user with their own resource usage is quit hard with a Linux beginner. The command PS has a lot of switches for sorting processes in different manner. We can simply sort the current executing processes with its CPU and Memory conception ratio. Also, here is a simple link for monitoring your server load “Load monitoring in Linux servers“
“ps command” and “top command” have a lot of options, here I am explaining some useful command combinations to find the resource(cpu, memory…) usages of users in the server.
It’s simply a static output of current resource usage in the server. You can use the grep command to separate users.
To list top 10 CPU usage processes with user
# ps -e -o pcpu,pid,user,args|sort -k1 -nr|head -10
Output
[root@Coimbatorewebhosting~]# ps -e -o pcpu,pid,user,args|sort -k1 -nr|head -10 %CPU PID USER COMMAND 0.0 9 root [rcu_sched] 0.0 9202 vnstat /usr/sbin/vnstatd -n 0.0 8 root [rcu_bh] 0.0 8907 root [kworker/u4:2] 0.0 7 root [migration/0] 0.0 749 postfix qmgr -l -t unix -u 0.0 746 root /usr/libexec/postfix/master -w 0.0 68 root [deferwq] 0.0 5 root [kworker/0:0H] [root@Coimbatorewebhosting~]#
Find out top 10 CPU consuming process
# ps -auxf|sort -nr -k3|head -10
Output
[root@Coimbatorewebhosting~]# ps -auxf|sort -nr -k3|head -10 vnstat 9202 0.0 0.0 7444 848 ? Ss Feb19 0:48 /usr/sbin/vnstatd -n USER PID %CPU %MEM VSZ RSS TTY STAT START TIME COMMAND root 9 0.0 0.0 0 0 ? S Feb19 3:56 \_ [rcu_sched] root 8907 0.0 0.0 0 0 ? S Feb19 0:00 \_ [kworker/u4:2] root 8 0.0 0.0 0 0 ? S Feb19 0:00 \_ [rcu_bh] root 746 0.0 0.2 89036 2172 ? Ss Feb19 0:04 /usr/libexec/postfix/master -w root 7 0.0 0.0 0 0 ? S Feb19 0:00 \_ [migration/0] root 68 0.0 0.0 0 0 ? S< Feb19 0:00 \_ [deferwq] root 5 0.0 0.0 0 0 ? S< Feb19 0:00 \_ [kworker/0:0H] root 494 0.0 0.0 110036 844 tty1 Ss+ Feb19 0:00 /sbin/agetty --noclear tty1 linux [root@Coimbatorewebhosting~]#
To list top 10 Memory consuming processes with user
# ps -e -o pmem,pid,user,args|sort -k1 -nr|head -10
Output
[root@Coimbatorewebhosting~]# ps -e -o pmem,pid,user,args|sort -k1 -nr|head -10 1.6 450 root /usr/bin/python -Es /usr/sbin/tuned -l -P 1.3 19168 root /usr/sbin/httpd -DFOREGROUND 0.8 457 polkitd /usr/lib/polkit-1/polkitd --no-debug 0.7 23926 apache /usr/sbin/httpd -DFOREGROUND 0.7 23925 apache /usr/sbin/httpd -DFOREGROUND 0.7 23924 apache /usr/sbin/httpd -DFOREGROUND 0.7 23424 apache /usr/sbin/httpd -DFOREGROUND 0.7 23388 apache /usr/sbin/httpd -DFOREGROUND 0.7 23387 apache /usr/sbin/httpd -DFOREGROUND 0.7 23386 apache /usr/sbin/httpd -DFOREGROUND [root@Coimbatorewebhosting~]#
Find out the top 10 memory consuming process
# ps -auxf|sort -nr -k4|head -10
Output
[root@Coimbatorewebhosting~]# ps -auxf|sort -nr -k4|head -10 root 450 0.0 1.6 553152 16436 ? Ssl Feb19 2:12 /usr/bin/python -Es /usr/sbin/tuned -l -P root 19168 0.0 1.3 330364 13248 ? Ss Feb19 1:01 /usr/sbin/httpd -DFOREGROUND polkitd 457 0.0 0.8 528308 8844 ? Ssl Feb19 0:00 /usr/lib/polkit-1/polkitd --no-debug apache 23926 0.0 0.7 330364 7784 ? S Feb26 0:00 \_ /usr/sbin/httpd -DFOREGROUND apache 23925 0.0 0.7 330364 7784 ? S Feb26 0:00 \_ /usr/sbin/httpd -DFOREGROUND apache 23924 0.0 0.7 330364 7788 ? S Feb26 0:00 \_ /usr/sbin/httpd -DFOREGROUND apache 23424 0.0 0.7 330364 7772 ? S Feb25 0:00 \_ /usr/sbin/httpd -DFOREGROUND apache 23388 0.0 0.7 330364 7788 ? S Feb25 0:00 \_ /usr/sbin/httpd -DFOREGROUND apache 23387 0.0 0.7 330364 7788 ? S Feb25 0:00 \_ /usr/sbin/httpd -DFOREGROUND apache 23386 0.0 0.7 330364 7768 ? S Feb25 0:00 \_ /usr/sbin/httpd -DFOREGROUND [root@Coimbatorewebhosting~]#
Find out every process running under a user
# ps -U user-name -u user-name u
Or
# ps -e -o pid,user,args|grep $username
Output
[root@Coimbatorewebhosting~]# ps -e -o pid,user,args|grep root
1 root /usr/lib/systemd/systemd --switched-root --system --deserialize 21
2 root [kthreadd]
3 root [ksoftirqd/0]
5 root [kworker/0:0H]
7 root [migration/0]
8 root [rcu_bh]
9 root [rcu_sched]
10 root [watchdog/0]
11 root [watchdog/1]
12 root [migration/1]
13 root [ksoftirqd/1]
15 root [kworker/1:0H]
17 root [kdevtmpfs]
18 root [netns]
To get a dynamic result you must use the ‘top‘ command instead of ‘ps’ or use the ‘watch‘ command along with the ‘ps’.
To show the process usage of a user with ‘top’
# top -u $username
Output
top - 11:47:03 up 7 days, 23:53, 2 users, load average: 0.00, 0.01, 0.05 Tasks: 76 total, 2 running, 74 sleeping, 0 stopped, 0 zombie %Cpu(s): 0.0 us, 0.2 sy, 0.0 ni, 99.8 id, 0.0 wa, 0.0 hi, 0.0 si, 0.0 st KiB Mem : 1012436 total, 370668 free, 68052 used, 573716 buff/cache KiB Swap: 2097148 total, 2097148 free, 0 used. 906684 avail Mem PID USER PR NI VIRT RES SHR S %CPU %MEM TIME+ COMMAND 23384 apache 20 0 330364 7768 1936 S 0.0 0.8 0:00.00 httpd 23385 apache 20 0 330364 7788 1932 S 0.0 0.8 0:00.00 httpd 23386 apache 20 0 330364 7768 1936 S 0.0 0.8 0:00.00 httpd 23387 apache 20 0 330364 7788 1932 S 0.0 0.8 0:00.00 httpd 23388 apache 20 0 330364 7788 1936 S 0.0 0.8 0:00.00 httpd 23424 apache 20 0 330364 7772 1936 S 0.0 0.8 0:00.00 httpd 23924 apache 20 0 330364 7788 1936 S 0.0 0.8 0:00.00 httpd 23925 apache 20 0 330364 7784 1932 S 0.0 0.8 0:00.00 httpd 23926 apache 20 0 330364 7784 1932 S 0.0 0.8 0:00.00 httpd
You can refer this “How to show process usage for single user with TOP command” for more details
To list top 10 CPU usage processes with user
# watch "ps -e -o pcpu,pid,user,args|sort -k1 -nr|head -10"
Output
0.4 24497 root watch ps -e -o pcpu,pid,user,args|sort -k1 -nr|head -10 %CPU PID USER COMMAND 0.0 9 root [rcu_sched] 0.0 9202 vnstat /usr/sbin/vnstatd -n 0.0 8 root [rcu_bh] 0.0 8907 root [kworker/u4:2] 0.0 7 root [migration/0] 0.0 749 postfix qmgr -l -t unix -u 0.0 746 root /usr/libexec/postfix/master -w 0.0 68 root [deferwq]
To list top 10 Memory consuming processes with user
# watch "ps -e -o pmem,pid,user,args|sort -k1 -nr|head -10"
instead you can use the grep command to separate users.
