How to show memory usage in Linux
You could use many tools to view memory usage information in Linux, and it's available in both graphical and command-line form.
Every graphical Linux distribution would bundle the desktop environment's default resource monitoring tools, such as System Monitor for GNOME or Resource Monitor for KDE. The bundled command-line tools, however, are similar for most Linux distributions.
The most common and widely available command-line tools to view memory usage in Linux are free and top. Both tools are handy when using the terminal, such as connecting to the system remotely via SSH or performing some automation tasks using shell scripts.
Steps to display memory usage information in Linux:
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Launch our preferred terminal application.
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Display basic memory usage information using free.
$ free total used free shared buff/cache available Mem: 2013428 999352 113610 6188 900376 842184 Swap: 969960 524 969436
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Display basic memory usage information using free in human readable format.
$ free -h total used free shared buff/cache available Mem: 1.9Gi 976Mi 111Mi 6.0Mi 879Mi 822Mi Swap: 947Mi 0.0Ki 946Mi
More options for free command:
$ free --help Usage: free [options] Options: -b, --bytes show output in bytes --kilo show output in kilobytes --mega show output in megabytes --giga show output in gigabytes --tera show output in terabytes --peta show output in petabytes -k, --kibi show output in kibibytes -m, --mebi show output in mebibytes -g, --gibi show output in gibibytes --tebi show output in tebibytes --pebi show output in pebibytes -h, --human show human-readable output --si use powers of 1000 not 1024 -l, --lohi show detailed low and high memory statistics -t, --total show total for RAM + swap -s N, --seconds N repeat printing every N seconds -c N, --count N repeat printing N times, then exit -w, --wide wide output --help display this help and exit -V, --version output version information and exit For more details see free(1).
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Display application memory usage using top.
$ top -n1 -o %MEM top - 16:25:49 up 40 min, 2 users, load average: 0.08, 0.23, 0.34 Tasks: 281 total, 1 running, 280 sleeping, 0 stopped, 0 zombie %Cpu(s): 5.9 us, 17.6 sy, 0.0 ni, 76.5 id, 0.0 wa, 0.0 hi, 0.0 si, 0.0 st MiB Mem : 1966.2 total, 108.4 free, 975.9 used, 881.9 buff/cache MiB Swap: 947.2 total, 946.7 free, 0.5 used. 822.1 avail Mem PID USER PR NI VIRT RES SHR S %CPU %MEM TIME+ COMMAND 1511 user 20 0 2575320 203944 87640 S 0.0 10.1 0:44.31 gnome-shell 1931 user 20 0 777408 119956 36288 S 0.0 6.0 0:03.91 gnome-software 2385 user 20 0 1393488 99916 54312 S 0.0 5.0 1:04.11 rhythmbox 2054 user 20 0 1043436 97064 44896 S 0.0 4.8 0:09.76 streamtuner2 1745 user 20 0 803280 56900 45324 S 0.0 2.8 0:00.44 evolution-alarm 1374 user 20 0 259016 54708 32968 S 0.0 2.7 0:15.65 Xorg 1930 user 20 0 986610 45828 33144 S 0.0 2.3 0:04.31 gnome-terminal- 1933 user 20 0 702652 39440 25932 S 0.0 2.0 0:00.31 seahorse 1771 user 20 0 344420 37420 29520 S 0.0 1.9 0:03.53 vmtoolsd 1788 user 20 0 750852 33624 28984 S 0.0 1.7 0:00.31 evolution-calen 1589 user 20 0 628356 32944 27610 S 0.0 1.6 0:00.12 goa-daemon 1801 user 20 0 695356 30780 27012 S 0.0 1.5 0:00.06 evolution-addre 2341 user 20 0 518056 29224 22776 S 0.0 1.5 0:00.29 update-notifier 1610 user 20 0 499596 28968 24656 S 0.0 1.4 0:00.12 evolution-sourc 641 root 20 0 676140 27736 13008 S 0.0 1.4 0:03.15 snapd 411 root 19 -1 58116 27384 25840 S 0.0 1.4 0:01.77 systemd-journal 1553 user 20 0 295756 26080 16944 S 0.0 1.3 0:00.77 ibus-extension- 1647 user 20 0 925768 25924 18964 S 0.0 1.3 0:00.48 gsd-media-keys 1660 user 20 0 515152 24880 18260 S 0.0 1.2 0:00.28 gsd-color 1640 user 20 0 369336 24764 18168 S 0.0 1.2 0:00.24 gsd-power 1666 user 20 0 367312 24732 17764 S 0.0 1.2 0:00.31 gsd-xsettings 1746 user 20 0 472812 23856 11652 S 0.0 1.2 0:00.25 tracker-store 1638 user 20 0 366800 23796 17368 S 0.0 1.2 0:00.23 gsd-keyboard 1557 user 20 0 218820 23624 17328 S 0.0 1.2 0:00.22 ibus-x11 1576 user 20 0 518380 23408 20332 S 0.0 1.2 0:00.09 gnome-shell-cal 1654 user 20 0 294528 23128 16672 S 0.0 1.1 0:00.22 gsd-wacom 1652 user 20 0 218360 22776 16488 S 0.0 1.1 0:00.75 gsd-clipboard 771 root 20 0 131004 21936 13820 S 0.0 1.1 0:00.31 unattended-upgr 1752 user 39 19 519912 21832 14252 S 0.0 1.1 0:00.17 tracker-miner-f 2034 root 20 0 389564 20808 17412 S 0.0 1.0 0:00.23 fwupd 1592 user 9 -11 2217220 19200 15460 S 5.9 1.0 2:47.65 pulseaudio 612 root 20 0 52112 18992 10972 S 0.0 0.9 0:00.23 networkd-dispat 632 root 20 0 424316 18976 16120 S 0.0 0.9 0:00.51 NetworkManager 1761 user 39 19 661240 18916 11748 S 0.0 0.9 0:00.15 tracker-miner-a 835 whoopsie 20 0 331610 15532 13660 S 0.0 0.8 0:00.07 whoopsie 1674 user 20 0 321672 15344 13440 S 0.0 0.8 0:00.02 gsd-datetime 1382 user 20 0 583368 15296 12536 S 0.0 0.8 0:00.22 gnome-session-b 1314 colord 20 0 257832 13772 8788 S 0.0 0.7 0:00.22 colord 1698 user 20 0 367052 13392 11628 S 0.0 0.7 0:00.02 gsd-printer 652 root 20 0 393988 12752 10204 S 0.0 0.6 0:00.18 udisksd 684 root 20 0 182624 11972 10412 S 0.0 0.6 0:00.12 cups-browsed 540 root 20 0 133576 11610 10264 S 0.0 0.6 0:02.97 vmtoolsd
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Display specific application memory usage using top
$ top -n1 -o %MEM | grep rhythmbox 2385 user 20 0 1393488 99916 54312 S 6.2 5.0 1:06.10 rhythmbox
More options for top command:
$ top -help procps-ng 3.3.15 Usage: top -hv | -bcEHiOSs1 -d secs -n max -u|U user -p pid(s) -o field -w [cols]
