[#]: collector: (lujun9972) [#]: translator: ( ) [#]: reviewer: ( ) [#]: publisher: ( ) [#]: url: ( ) [#]: subject: (How to Find Out Top Memory Consuming Processes in Linux) [#]: via: (https://www.2daygeek.com/linux-find-top-memory-consuming-processes/) [#]: author: (Magesh Maruthamuthu https://www.2daygeek.com/author/magesh/) How to Find Out Top Memory Consuming Processes in Linux ====== You may have seen your system consumes too much of memory many times. If that’s the case, what would be the best thing you can do to identify processes that consume too much memory on a Linux machine. I believe, you may have run one of the below commands to check it out. If not, what is the other commands you tried? I would request you to update it in the comment section, it may help other users. This can be easily identified using the **[top command][1]** and the **[ps command][2]**. I used to check both commands simultaneously, and both were given the same result. So i suggest you to use one of the command that you like. ### 1) How to Find Top Memory Consuming Process in Linux Using the ps Command The ps command is used to report a snapshot of the current processes. The ps command stands for process status. This is a standard Linux application that looks for information about running processes on a Linux system. It is used to list the currently running processes and their process ID (PID), process owner name, process priority (PR), and the absolute path of the running command, etc,. The below ps command format provides you more information about top memory consumption process. ``` # ps aux --sort -rss | head USER PID %CPU %MEM VSZ RSS TTY STAT START TIME COMMAND mysql 1064 3.2 5.4 886076 209988 ? Ssl Oct25 62:40 /usr/sbin/mysqld varnish 23396 0.0 2.9 286492 115616 ? SLl Oct25 0:42 /usr/sbin/varnishd -P /var/run/varnish.pid -f /etc/varnish/default.vcl -a :82 -T 127.0.0.1:6082 -S /etc/varnish/secret -s malloc,256M named 1105 0.0 2.7 311712 108204 ? Ssl Oct25 0:16 /usr/sbin/named -u named -c /etc/named.conf nobody 23377 0.2 2.3 153096 89432 ? S Oct25 4:35 nginx: worker process nobody 23376 0.1 2.1 147096 83316 ? S Oct25 2:18 nginx: worker process root 23375 0.0 1.7 131028 66764 ? Ss Oct25 0:01 nginx: master process /usr/sbin/nginx -c /etc/nginx/nginx.conf nobody 23378 0.0 1.6 130988 64592 ? S Oct25 0:00 nginx: cache manager process root 1135 0.0 0.9 86708 37572 ? S 05:37 0:20 cwpsrv: worker process root 1133 0.0 0.9 86708 37544 ? S 05:37 0:05 cwpsrv: worker process ``` Use the below ps command format to include only specific information about the process of memory consumption in the output. ``` # ps -eo pid,ppid,%mem,%cpu,cmd --sort=-%mem | head PID PPID %MEM %CPU CMD 1064 1 5.4 3.2 /usr/sbin/mysqld 23396 23386 2.9 0.0 /usr/sbin/varnishd -P /var/run/varnish.pid -f /etc/varnish/default.vcl -a :82 -T 127.0.0.1:6082 -S /etc/varnish/secret -s malloc,256M 1105 1 2.7 0.0 /usr/sbin/named -u named -c /etc/named.conf 23377 23375 2.3 0.2 nginx: worker process 23376 23375 2.1 0.1 nginx: worker process 3625 977 1.9 0.0 /usr/local/bin/php-cgi /home/daygeekc/public_html/index.php 23375 1 1.7 0.0 nginx: master process /usr/sbin/nginx -c /etc/nginx/nginx.conf 23378 23375 1.6 0.0 nginx: cache manager process 1135 3034 0.9 0.0 cwpsrv: worker process ``` If you want to see only the command name instead of the absolute path of the command, use the ps command format below. ``` # ps -eo pid,ppid,%mem,%cpu,comm --sort=-%mem | head PID PPID %MEM %CPU COMMAND 1064 1 5.4 3.2 mysqld 23396 23386 2.9 0.0 cache-main 1105 1 2.7 0.0 named 23377 23375 2.3 0.2 nginx 23376 23375 2.1 0.1 nginx 23375 1 1.7 0.0 nginx 23378 23375 1.6 0.0 nginx 1135 3034 0.9 0.0 cwpsrv 1133 3034 0.9 0.0 cwpsrv ``` ### 2) How to Find Out Top Memory Consuming Process in Linux Using the top Command The Linux top command is the best and most well known command that everyone uses to monitor Linux system performance. It displays a real-time view of the system process running on the interactive interface. But if you want to find top memory consuming process then **[use the top command in the batch mode][3]**. You should properly **[understand the top command output][4]** to fix the performance issue in system. ``` # top -c -b -o +%MEM | head -n 20 | tail -15 PID USER PR NI VIRT RES SHR S %CPU %MEM TIME+ COMMAND 1064 mysql 20 0 886076 209740 8388 S 0.0 5.4 62:41.20 /usr/sbin/mysqld 23396 varnish 20 0 286492 115616 83572 S 0.0 3.0 0:42.24 /usr/sbin/varnishd -P /var/run/varnish.pid -f /etc/varnish/default.vcl -a :82 -T 127.0.0.1:6082 -S /etc/varnish/secret -s malloc,256M 1105 named 20 0 311712 108204 2424 S 0.0 2.8 0:16.41 /usr/sbin/named -u named -c /etc/named.conf 23377 nobody 20 0 153240 89432 2432 S 0.0 2.3 4:35.74 nginx: worker process 23376 nobody 20 0 147096 83316 2416 S 0.0 2.1 2:18.09 nginx: worker process 23375 root 20 0 131028 66764 1616 S 0.0 1.7 0:01.07 nginx: master process /usr/sbin/nginx -c /etc/nginx/nginx.conf 23378 nobody 20 0 130988 64592 592 S 0.0 1.7 0:00.51 nginx: cache manager process 1135 root 20 0 86708 37572 2252 S 0.0 1.0 0:20.18 cwpsrv: worker process 1133 root 20 0 86708 37544 2212 S 0.0 1.0 0:05.94 cwpsrv: worker process 3034 root 20 0 86704 36740 1452 S 0.0 0.9 0:00.09 cwpsrv: master process /usr/local/cwpsrv/bin/cwpsrv 1067 nobody 20 0 1356200 31588 2352 S 0.0 0.8 0:56.06 /usr/local/apache/bin/httpd -k start 977 nobody 20 0 1356088 31268 2372 S 0.0 0.8 0:30.44 /usr/local/apache/bin/httpd -k start 968 nobody 20 0 1356216 30544 2348 S 0.0 0.8 0:19.95 /usr/local/apache/bin/httpd -k start ``` If you only want to see the command name instead of the absolute path of the command, use the below top command format. ``` # top -b -o +%MEM | head -n 20 | tail -15 PID USER PR NI VIRT RES SHR S %CPU %MEM TIME+ COMMAND 1064 mysql 20 0 886076 210340 8388 S 6.7 5.4 62:40.93 mysqld 23396 varnish 20 0 286492 115616 83572 S 0.0 3.0 0:42.24 cache-main 1105 named 20 0 311712 108204 2424 S 0.0 2.8 0:16.41 named 23377 nobody 20 0 153240 89432 2432 S 13.3 2.3 4:35.74 nginx 23376 nobody 20 0 147096 83316 2416 S 0.0 2.1 2:18.09 nginx 23375 root 20 0 131028 66764 1616 S 0.0 1.7 0:01.07 nginx 23378 nobody 20 0 130988 64592 592 S 0.0 1.7 0:00.51 nginx 1135 root 20 0 86708 37572 2252 S 0.0 1.0 0:20.18 cwpsrv 1133 root 20 0 86708 37544 2212 S 0.0 1.0 0:05.94 cwpsrv 3034 root 20 0 86704 36740 1452 S 0.0 0.9 0:00.09 cwpsrv 1067 nobody 20 0 1356200 31588 2352 S 0.0 0.8 0:56.04 httpd 977 nobody 20 0 1356088 31268 2372 S 0.0 0.8 0:30.44 httpd 968 nobody 20 0 1356216 30544 2348 S 0.0 0.8 0:19.95 httpd ``` ### 3) Bonus Tips: How to Find Out Top Memory Consuming Process in Linux Using the ps_mem Command The **[ps_mem utility][5]** is used to display the core memory used per program (not per process). This utility allows you to check how much memory is used per program. It calculates the amount of private and shared memory against a program and returns the total used memory in the most appropriate way. It uses the following logic to calculate RAM usage. Total RAM = sum (private RAM for program processes) + sum (shared RAM for program processes) ``` # ps_mem Private + Shared = RAM used Program 128.0 KiB + 27.5 KiB = 155.5 KiB agetty 228.0 KiB + 47.0 KiB = 275.0 KiB atd 284.0 KiB + 53.0 KiB = 337.0 KiB irqbalance 380.0 KiB + 81.5 KiB = 461.5 KiB dovecot 364.0 KiB + 121.5 KiB = 485.5 KiB log 520.0 KiB + 65.5 KiB = 585.5 KiB auditd 556.0 KiB + 60.5 KiB = 616.5 KiB systemd-udevd 732.0 KiB + 48.0 KiB = 780.0 KiB crond 296.0 KiB + 524.0 KiB = 820.0 KiB avahi-daemon (2) 772.0 KiB + 51.5 KiB = 823.5 KiB systemd-logind 940.0 KiB + 162.5 KiB = 1.1 MiB dbus-daemon 1.1 MiB + 99.0 KiB = 1.2 MiB pure-ftpd 1.2 MiB + 100.5 KiB = 1.3 MiB master 1.3 MiB + 198.5 KiB = 1.5 MiB pickup 1.3 MiB + 198.5 KiB = 1.5 MiB bounce 1.3 MiB + 198.5 KiB = 1.5 MiB pipe 1.3 MiB + 207.5 KiB = 1.5 MiB qmgr 1.4 MiB + 198.5 KiB = 1.6 MiB cleanup 1.3 MiB + 299.5 KiB = 1.6 MiB trivial-rewrite 1.5 MiB + 145.0 KiB = 1.6 MiB config 1.4 MiB + 291.5 KiB = 1.6 MiB tlsmgr 1.4 MiB + 308.5 KiB = 1.7 MiB local 1.4 MiB + 323.0 KiB = 1.8 MiB anvil (2) 1.3 MiB + 559.0 KiB = 1.9 MiB systemd-journald 1.8 MiB + 240.5 KiB = 2.1 MiB proxymap 1.9 MiB + 322.5 KiB = 2.2 MiB auth 2.4 MiB + 88.5 KiB = 2.5 MiB systemd 2.8 MiB + 458.5 KiB = 3.2 MiB smtpd 2.9 MiB + 892.0 KiB = 3.8 MiB bash (2) 3.3 MiB + 555.5 KiB = 3.8 MiB NetworkManager 4.1 MiB + 233.5 KiB = 4.3 MiB varnishd 4.0 MiB + 662.0 KiB = 4.7 MiB dhclient (2) 4.3 MiB + 623.5 KiB = 4.9 MiB rsyslogd 3.6 MiB + 1.8 MiB = 5.5 MiB sshd (3) 5.6 MiB + 431.0 KiB = 6.0 MiB polkitd 13.0 MiB + 546.5 KiB = 13.6 MiB tuned 22.5 MiB + 76.0 KiB = 22.6 MiB lfd - sleeping 30.0 MiB + 6.2 MiB = 36.2 MiB php-fpm (6) 5.7 MiB + 33.5 MiB = 39.2 MiB cwpsrv (3) 20.1 MiB + 25.3 MiB = 45.4 MiB httpd (5) 104.7 MiB + 156.0 KiB = 104.9 MiB named 112.2 MiB + 479.5 KiB = 112.7 MiB cache-main 69.4 MiB + 58.6 MiB = 128.0 MiB nginx (4) 203.4 MiB + 309.5 KiB = 203.7 MiB mysqld --------------------------------- 775.8 MiB ================================= ``` -------------------------------------------------------------------------------- via: https://www.2daygeek.com/linux-find-top-memory-consuming-processes/ 作者：[Magesh Maruthamuthu][a] 选题：[lujun9972][b] 译者：[译者ID](https://github.com/译者ID) 校对：[校对者ID](https://github.com/校对者ID) 本文由 [LCTT](https://github.com/LCTT/TranslateProject) 原创编译，[Linux中国](https://linux.cn/) 荣誉推出 [a]: https://www.2daygeek.com/author/magesh/ [b]: https://github.com/lujun9972 [1]: https://www.2daygeek.com/linux-top-command-linux-system-performance-monitoring-tool/ [2]: https://www.2daygeek.com/linux-ps-command-find-running-process-monitoring/ [3]: https://www.2daygeek.com/linux-run-execute-top-command-in-batch-mode/ [4]: https://www.2daygeek.com/understanding-linux-top-command-output-usage/ [5]: https://www.2daygeek.com/ps_mem-report-core-memory-usage-accurately-in-linux/