Memory usage calculation for Linux

How is the total memory utilization calculated for a Linux server monitor?

Memory utilization is calculated using the "free" command. The output of this command varies according to the Linux distribution used.

Case 1:
Memory Utilized = ( (Total - Free Memory) / Total * 100 )
where,
Free Memory = ( Total - Used + Buffer + Cache )
Eg:

Free Memory = (16313900 - 7857128 + 203152 + 4381116) = 13041040

Memory Utilized = ( (Total-Free) / Total * 100) = 20.06%

Case 2:
This is applicable when using Linux flavors including Centos/Redhat 7+, Ubuntu 16+ etc. 
Eg:

Total Memory = 16330916     Free Memory = Available Memory = 9157464
Thus, Memory Utilized = ( ( Total - Free Memory ) / Total * 100 )
Memory Utilized = 43.92%


Note: The value obtained can be cross verified with the System Monitor (a default tool present in Linux servers for basic metrics monitoring) output.


Related Articles:

    • Related Articles

    • No data for service and process in Windows server monitor

      If you see "No Data" for process and service metrics (such as CPU or memory usage of monitored services) in the Site24x7 Windows server monitor user interface, follow the troubleshooting steps below. Run PowerShell Commands Open PowerShell as ...
    • Monitor count

      Monitor count refers to the number of websites or servers you add for monitoring. If you add ESX servers, Site24x7 automatically discovers all the available VMs on each ESX server and count it as a separate VM monitor, thus increasing your total ...
    • Amendments to Site24x7 Monitor Names

      We've recently renamed a few of our Monitors to help keep in sync with the current IT and DevOps trends. The new monitor names are designed to correctly resonate with the IT & DevOps crowd. We've made necessary changes in the Web client, Help ...
    • How is the basic and advanced monitor count calculated in the Site24x7 web client?

      Site24x7 licensing and pricing works based on the type of monitor. Monitors are classified as basic and advanced monitors. The Super Admins can view a detailed breakdown of license usage with License Usage Summary. The monitors in your Site24x7 ...
    • Monitor and validate DNS IP changes using regex

      DNS administrators often monitor their DNS servers to detect changes in domain resolution and ensure IP mappings remain secure and accurate. Problem When your organization adds or modifies an IP address for your domain name, it’s critical to: Be ...