Introduction to the free
Command in Linux
The free
command in Linux is a simple utility used to display information about system memory usage, including free, used, and available memory. It is a crucial tool for monitoring system performance and diagnosing memory-related issues. In the ChromeOS Linux Environment (Crostini), free
provides insights into how your Linux container is utilizing memory.
Syntax and Usage
The basic syntax of the free
command is as follows:
free [options]
options
: Flags to modify the behavior and format of the output.
Common Use Cases
-
Display memory usage in default format:
free
-
Display memory usage in human-readable format:
free -h
This formats the output using units like KB, MB, or GB for easier readability.
-
Show memory usage with details about buffer and cache:
free -b
This displays memory usage in bytes.
-
Continuous monitoring of memory usage:
Although
free
does not natively support continuous monitoring, you can pair it withwatch
:watch free -h
Understanding the Output
The free
command displays several key metrics:
total
: Total installed memory.used
: Memory currently in use.free
: Unused memory.shared
: Memory used by shared resources.buff/cache
: Memory used by buffers and cache.available
: Memory available for new processes without swapping.
Useful Options
-h
: Human-readable format.-b
: Display memory usage in bytes.-k
: Display memory usage in kilobytes (default).-m
: Display memory usage in megabytes.-g
: Display memory usage in gigabytes.
Special Notes for ChromeOS Linux Environment
In the ChromeOS Linux Environment, the free
command reflects the memory usage of the Crostini container. Monitoring memory usage is particularly important when running resource-intensive applications, as the container shares system resources with ChromeOS.
To ensure smooth performance, keep an eye on the used
and available
memory metrics, especially when running multiple applications or compiling software within the Linux container.
Conclusion
The free
command is an essential tool for understanding and managing memory usage in Linux. Whether you're diagnosing performance issues or optimizing resource allocation, free
provides critical insights into system memory in the ChromeOS Linux Environment.