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system:memory:usage
The command "free -m" is used to display the amount of free and used memory in a Linux system, measured in megabytes.
Here's a breakdown of the command:
- "free" is the name of the command itself.
- "-m" is an option passed to the command. The "-m" option is used to display the memory values in megabytes.
When you execute the "free -m" command in a terminal or command prompt, it will provide an output similar to the following:
total used free shared buffers cached
Mem: 7976 3730 4246 0 57 1850 -/+ buffers/cache: 1823 6153 Swap: 4095 0 4095
The output is divided into three sections:
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Memory: This section provides information about the system's physical memory (RAM). It includes the following columns:
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Total: The total physical memory (RAM) available.
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Used: The amount of RAM being used by the system.
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Free: The amount of unallocated RAM available for use.
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Shared: The amount of shared memory available.
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Buffers: The amount of memory used by buffered data (disk-related transfers).
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Cached: The amount of memory used by the page cache (disk-related data that is kept in memory).
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-/+ buffers/cache: This section provides information on the RAM utilization, excluding the memory used by buffers and cache. It includes the following columns:
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Used: The amount of RAM being actively used by processes.
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Free: The amount of unallocated RAM available for use.
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Swap: This section provides information about the system's swap space. Swap space is an extension of physical memory that is used when the RAM is full. It includes the following columns:
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Total: The total swap space available.
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Used: The amount of swap space being used.
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Free: The amount of unallocated swap space available.
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Overall, the "free -m" command helps to monitor the memory usage of a Linux system, allowing users to understand how memory is being utilized and if there are any potential constraints or bottlenecks.