top command for system monitoring.
TOP is one of the system load monitoring command.Others are ps ,iostat and vmstat.
using top command you can kill the process causing high load on the system.
$top
enter top and you will see the following screen
top - 05:44:25 up 6:32, 2 users, load average: 0.06, 0.18, 0.15
Tasks: 90 total, 1 running, 89 sleeping, 0 stopped, 0 zombie
Cpu(s): 0.8%us, 0.0%sy, 0.0%ni, 99.0%id, 0.0%wa, 0.2%hi, 0.0%si, 0.0%st
Mem: 484188k total, 476212k used, 7976k free, 63728k buffers
Swap: 489940k total, 104k used, 489836k free, 214956k cached
PID USER PR NI VIRT RES SHR S %CPU %MEM TIME+ COMMAND
3663 nandam 15 0 36852 15m 9.8m S 1 3.2 0:00.32 gnome-terminal
2493 root 15 0 63456 22m 8716 S 0 4.7 5:55.30 Xorg
2668 nandam 15 0 15328 2272 1436 S 0 0.5 0:11.07 gnome-screensav
1 root 15 0 2036 720 620 S 0 0.1 0:01.28 init
2 root RT 0 0 0 0 S 0 0.0 0:00.00 migration/0
3 root 34 19 0 0 0 S 0 0.0 0:04.44 ksoftirqd/0
4 root RT 0 0 0 0 S 0 0.0 0:00.00 migration/1
5 root 34 19 0 0 0 S 0 0.0 0:00.48 ksoftirqd/1
6 root 10 -5 0 0 0 S 0 0.0 0:00.12 events/0
7 root 10 -5 0 0 0 S 0 0.0 0:00.00 events/1
8 root 10 -5 0 0 0 S 0 0.0 0:00.00 khelper
9 root 10 -5 0 0 0 S 0 0.0 0:00.00 kthread
13 root 12 -5 0 0 0 S 0 0.0 0:00.00 kblockd/0
14 root 10 -5 0 0 0 S 0 0.0 0:00.00 kblockd/1
15 root 15 -5 0 0 0 S 0 0.0 0:00.00 kacpid
92 root 10 -5 0 0 0 S 0 0.0 0:00.00 kseriod
134 root 15 0 0 0 0 S 0 0.0 0:00.19 pdflush
You can see the process are listed in descending order of CPU usage. Top always displays a dyanamic list of processes. In the top portion of the report it displays the total uptime of the system, no of users , no of processes running and the total CPU,memory adn swap space usage of the system.
You can sort the output in the descending order of memory usage by hitting M. to return to intial report hit M again.
if dont want the idle processes to be displayed hit i. To return to initial output press i again.
If you want to see the process of single user, press u and enter the user name and to revert back press u again and donot enter any username.
You can kill the process by pressing K and enter the process id .
For More info refer top manual
to exit from TOP command press ‘q’ or ctrl+c.