{"id":1924,"date":"2020-11-18T21:09:24","date_gmt":"2020-11-18T21:09:24","guid":{"rendered":"https:\/\/linuxways.net\/?p=1924"},"modified":"2020-11-20T15:20:52","modified_gmt":"2020-11-20T15:20:52","slug":"4-ways-to-check-memory-usage-in-centos-8","status":"publish","type":"post","link":"https:\/\/linuxways.net\/de\/centos\/4-ways-to-check-memory-usage-in-centos-8\/","title":{"rendered":"4 ways to check memory usage in CentOS 8"},"content":{"rendered":"

Sometimes, when you are working on a Linux environment, you may need to install some new packages on a daily basis. For this purpose, you need to check memory usage to install a new program. So, you should know how to check available and installed RAM or memory on your system.<\/p>\n

In this article, we will explore some major commands that are useful to check the memory usage in CentOS 8.<\/p>\n

Prerequisites<\/strong><\/h2>\n

You should have root account or sudo privileges to run the administrative commands. <\/p>\n

You can check the memory usage on your CentOS 8 Linux system by using the following five different commands which we will explain one by one in detail:<\/p>\n

    \n
  1. Cat command<\/li>\n
  2. Free command<\/li>\n
  3. Vmstat command<\/li>\n
  4. Top command<\/li>\n
  5. Htop command<\/li>\n<\/ol>\n

    Use of cat command<\/strong><\/h2>\n

    Open the terminal and type cat \/proc\/meminfo on the terminal window. It will open the \/proc\/meminfo virtual file that displays the information about used and available memory.<\/p>\n

    <\/p>\n

    It displays the real-time information about the memory usage as well as the shared memory which is used by the kernel, buffers details.  <\/p>\n

    Use of free command<\/strong><\/h2>\n

    When you will execute the free command on the terminal, it will display the following information:<\/p>\n

    <\/p>\n

    The above-displayed image contains different terms that we will explain one by one as follows:<\/p>\n

    Data represented in the above image, such as under the used, available, and swap memory terms are in kilobytes.<\/p>\n

    total <\/strong>represents the total memory installed on your system<\/p>\n

    used<\/strong> how much memory is currently using by running tasks ( you can calculate used memory = total \u2013 free \u2013 buffer\/cache)<\/p>\n

    free <\/strong>represents the memory that is not being used<\/p>\n

    shared<\/strong> shows the amount of memory that is being shared by different multiple processes<\/p>\n

    Buffers <\/strong>amount of memory which is reserved by the OS kernel. This memory is further allocated as buffers when process will need<\/p>\n

    cached <\/strong>how much memory is used to store recently files in RAM<\/p>\n

    buff\/cache <\/strong>Buffers + Cache memory<\/p>\n

    Available <\/strong>shows memory which is available for starting new tasks, without swapping.<\/p>\n

    Using the following command you can explore a complete description and all options of free command:<\/p>\n

    $ man free<\/p>\n

    <\/p>\n

    Use of vmstat Command<\/strong><\/h2>\n

    The vmstat command is used to display complete statistics of virtual memory.<\/p>\n

    This command gives the information about the memory, system processes, CPU activity, paging, block IO, and traps.<\/p>\n

    <\/p>\n

    Use of top command<\/strong><\/h2>\n

    Top command is a very useful command line tool that is used to examine the memory and CPU usage per process. It displays the information about the following things:<\/p>\n