Overview
This article provides information on understanding the output when you login to a linux server (with an SSH access) and execute the following command:
free -m
Information
The output of the command is similar to following:
where,
- Total- Mem : Total Main Memory Allocated to the system
- Total - Swap: Total Swap Memory allocated to the system. This will be borrowed from the Storage, if memory consumption is more than Main memory
-
Used - Mem: Main Memory in use. It is ‘calculated’ as
Used Memory = total - free - buffers - cache
- Used - Swap: Swap Memory borrowed in case the demand for Memory is more than the available memory
-
Free - Mem: This is unused memory, obtained by parsing
/proc/meminfo
- Free - Swap: Swap Memory that is not in use at the moment.
- Shared: Used (mostly) by tmpfs file system for interprocess common data or objects.
- Buff/cache: Memory reserved/used by kernel buffers and cache, but maybe made available if not in use and required by another application.
- Available: Estimation of how much memory is available for a new application to use, without using Swap memory.
More information may be taken from the free RHEL manual or forums.
Priyanka Bhotika
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