To monitor which process is using swap, you can use the top command:
Log in to Advanced shell (bash).
Type the following command to enter the top utility:
# top
[root@unixonline]# top
top - 01:10:24 up 230 days, 9:05, 9 users, load average: 0.00, 0.01, 0.05
Tasks: 220 total, 1 running, 219 sleeping, 0 stopped, 0 zombie
%Cpu(s): 0.1 us, 0.1 sy, 0.0 ni, 99.8 id, 0.0 wa, 0.0 hi, 0.0 si, 0.0 st
KiB Mem : 8173900 total, 208380 free, 1598880 used, 6366640 buff/cache
KiB Swap: 0 total, 0 free, 0 used. 5833596 avail Mem
PID USER PR NI VIRT RES SHR S %CPU %MEM TIME+ COMMAND
24275 dirsrv 20 0 1081116 170152 44012 S 0.3 2.1 1198:56 ns-slapd
31097 root 20 0 162104 2352 1592 R 0.3 0.0 0:00.02 top
1 root 20 0 191372 4416 2616 S 0.0 0.1 80:15.97 systemd
2 root 20 0 0 0 0 S 0.0 0.0 0:15.50 kthreadd
4 root 0 -20 0 0 0 S 0.0 0.0 0:00.00 kworker/0:+
6 root 20 0 0 0 0 S 0.0 0.0 2:34.12 ksoftirqd/0
7 root rt 0 0 0 0 S 0.0 0.0 0:52.99 migration/0
8 root 20 0 0 0 0 S 0.0 0.0 0:00.00 rcu_bh
9 root 20 0 0 0 0 S 0.0 0.0 24:10.74 rcu_sched
10 root 0 -20 0 0 0 S 0.0 0.0 0:00.00 lru-add-dr+
11 root rt 0 0 0 0 S 0.0 0.0 1:33.41 watchdog/0
12 root rt 0 0 0 0 S 0.0 0.0 1:17.54 watchdog/1
13 root rt 0 0 0 0 S 0.0 0.0 0:34.23 migration/1
14 root 20 0 0 0 0 S 0.0 0.0 2:10.22 ksoftirqd/1
16 root 0 -20 0 0 0 S 0.0 0.0 0:00.00 kworker/1:+
17 root rt 0 0 0 0 S 0.0 0.0 1:15.58 watchdog/2
18 root rt 0 0 0 0 S 0.0 0.0 0:28.49 migration/2
Press f to edit the columns display.
Press down to navigate down to the SWAP = Swapped Size (KiB) row.
Press right to select it for move.
Press up to move SWAP = Swapped Size (KiB) just directly above the COMMAND = Command Name/Line row.
Press Enter to commit.
Press space to add SWAP = Swapped Size (KiB) as a column to the top output. You may observe an additional * next to SWAP similar to the following example:
- SWAP = Swapped Size (KiB)
- COMMAND = Command Name/Line
Press Esc to exit edit mode.
Press shift+w to save the changes to the ~/.toprc file(top’s Config File). You may observe a momentary message similar to the following:
Wrote configuration to ‘/root/.toprc’
[root@unixonline]# ls -al .toprc -rw-r--r-- 1 root root 966 Dec 18 01:12 .toprc
The next time you start top, the swap column is displayed according to the settings in .toprc file.
[root@unixonline]# top
top - 01:14:37 up 230 days, 9:10, 9 users, load average: 0.00, 0.01, 0.05
Tasks: 219 total, 1 running, 218 sleeping, 0 stopped, 0 zombie
%Cpu(s): 0.0 us, 2.9 sy, 0.0 ni, 97.1 id, 0.0 wa, 0.0 hi, 0.0 si, 0.0 st
KiB Mem : 8173900 total, 210268 free, 1596928 used, 6366704 buff/cache
KiB Swap: 0 total, 0 free, 0 used. 5835556 avail Mem
PID USER PR NI VIRT RES SHR S %CPU %MEM TIME+ SWAP
31317 root 20 0 162104 2284 1560 R 6.2 0.0 0:00.02 0
1 root 20 0 191372 4416 2616 S 0.0 0.1 80:16.02 0
2 root 20 0 0 0 0 S 0.0 0.0 0:15.50 0
4 root 0 -20 0 0 0 S 0.0 0.0 0:00.00 0
6 root 20 0 0 0 0 S 0.0 0.0 2:34.17 0
7 root rt 0 0 0 0 S 0.0 0.0 0:52.99 0
8 root 20 0 0 0 0 S 0.0 0.0 0:00.00 0
9 root 20 0 0 0 0 S 0.0 0.0 24:10.75 0
10 root 0 -20 0 0 0 S 0.0 0.0 0:00.00 0
11 root rt 0 0 0 0 S 0.0 0.0 1:33.41 0
12 root rt 0 0 0 0 S 0.0 0.0 1:17.54 0
13 root rt 0 0 0 0 S 0.0 0.0 0:34.23 0
14 root 20 0 0 0 0 S 0.0 0.0 2:10.22 0
16 root 0 -20 0 0 0 S 0.0 0.0 0:00.00 0
17 root rt 0 0 0 0 S 0.0 0.0 1:15.58 0
18 root rt 0 0 0 0 S 0.0 0.0 0:28.49 0
19 root 20 0 0 0 0 S 0.0 0.0 0:21.53 0