Display processes using swap space
Use the following command to simply display processes using swap space. This list will be sorted by process id by default due to a way find command return its results, which are parsed by awk utility.
$ find /proc -maxdepth 2 -path "/proc/[0-9]*/status" -readable -exec awk -v FS=":" '{process[$1]=$2;sub(/^[ \t]+/,"",process[$1]);} END {if(process["VmSwap"] && process["VmSwap"] != "0 kB") printf "%10s %-30s %20s\n",process["Pid"],process["Name"],process["VmSwap"]}' '{}' \;
[..]
1 systemd 12 kB
555 systemd-udevd 52 kB
957 AgentSvc 448 kB
966 accounts-daemon 8 kB
978 networkd-dispat 256 kB
981 dbus-daemon 16 kB
987 cron 4 kB
1134 gdm3 28 kB
1139 lwsmd 84 kB
1270 unattended-upgr 388 kB
1471 rtkit-daemon 4 kB
1731 whoopsie 12 kB
1734 kerneloops 4 kB
1868 (sd-pam) 12 kB
[..]
Display processes using swap space sorted by used space
Use additional awk instance to add temporary column at the beginning, so data could be easily sorted by used swap space in ascending order.
$ find /proc -maxdepth 2 -path "/proc/[0-9]*/status" -readable -exec awk -v FS=":" '{process[$1]=$2;sub(/^[ \t]+/,"",process[$1]);} END {if(process["VmSwap"] && process["VmSwap"] != "0 kB") printf "%10s %-30s %20s\n",process["Pid"],process["Name"],process["VmSwap"]}' '{}' \; | awk '{print $(NF-1),$0}' | sort -h | cut -d " " -f2-
[..]
1471 rtkit-daemon 4 kB
1734 kerneloops 4 kB
987 cron 4 kB
966 accounts-daemon 8 kB
1731 whoopsie 12 kB
1868 (sd-pam) 12 kB
1 systemd 12 kB
981 dbus-daemon 16 kB
1134 gdm3 28 kB
555 systemd-udevd 52 kB
1139 lwsmd 84 kB
978 networkd-dispat 256 kB
1270 unattended-upgr 388 kB
957 AgentSvc 448 kB
[..]
Display top ten processes using swap space
The following command will sort processes by used swap space in descending order, then execute head utility to limit number of records.
$ find /proc -maxdepth 2 -path "/proc/[0-9]*/status" -readable -exec awk -v FS=":" '{process[$1]=$2;sub(/^[ \t]+/,"",process[$1]);} END {if(process["VmSwap"] && process["VmSwap"] != "0 kB") printf "%10s %-30s %20s\n",process["Pid"],process["Name"],process["VmSwap"]}' '{}' \; | awk '{print $(NF-1),$0}' | sort -hr | head | cut -d " " -f2-
957 AgentSvc 448 kB
1270 unattended-upgr 388 kB
978 networkd-dispat 256 kB
1139 lwsmd 84 kB
555 systemd-udevd 52 kB
1134 gdm3 28 kB
981 dbus-daemon 16 kB
1 systemd 12 kB
1868 (sd-pam) 12 kB
1731 whoopsie 12 kB
Display top ten processes using swap space with percentage values
Read (see 1st command) or calculate (see 2nd command) total available swap space to calculate and display per process percentage swap usage. Both of these commands are equivalent.
$ find /proc -maxdepth 2 -path "/proc/[0-9]*/status" -readable -exec awk -v FS=":" -v TOTSWP="$(cat /proc/meminfo | sed -n -e "s/^SwapTotal:[ ]*\([0-9]*\) kB/\1/p")" '{process[$1]=$2;sub(/^[ \t]+/,"",process[$1]);} END {if(process["VmSwap"] && process["VmSwap"] != "0 kB") {used_swap=process["VmSwap"];sub(/[ a-zA-Z]+/,"",used_swap);percent=(used_swap/TOTSWP*100); printf "%10s %-30s %20s %6.2f%\n",process["Pid"],process["Name"],process["VmSwap"],percent} }' '{}' \; | awk '{print $(NF-2),$0}' | sort -hr | head | cut -d " " -f2-
$ find /proc -maxdepth 2 -path "/proc/[0-9]*/status" -readable -exec awk -v FS=":" -v TOTSWP="$(cat /proc/swaps | sed 1d | awk 'BEGIN{sum=0} {sum=sum+$(NF-2)} END{print sum}')" '{process[$1]=$2;sub(/^[ \t]+/,"",process[$1]);} END {if(process["VmSwap"] && process["VmSwap"] != "0 kB") {used_swap=process["VmSwap"];sub(/[ a-zA-Z]+/,"",used_swap);percent=(used_swap/TOTSWP*100); printf "%10s %-30s %20s %6.2f%\n",process["Pid"],process["Name"],process["VmSwap"],percent} }' '{}' \; | awk '{print $(NF-2),$0}' | sort -hr | head | cut -d " " -f2-
957 AgentSvc 448 kB 0.02%
1270 unattended-upgr 388 kB 0.02%
978 networkd-dispat 256 kB 0.02%
1139 lwsmd 84 kB 0.01%
555 systemd-udevd 52 kB 0.01%
1134 gdm3 28 kB 0.01%
981 dbus-daemon 16 kB 0.01%
1 systemd 12 kB 0.01%
1868 (sd-pam) 12 kB 0.01%
1731 whoopsie 12 kB 0.01%
awk is beautiful!