systemd-analyze:tldr:4b33a

The command "systemd-analyze critical-chain" is used in a Linux system running systemd to analyze the critical chain of the system's startup process.

When a Linux system starts up, many services and units are started simultaneously or in a specific order. The critical chain represents the series of units that are required to be started before the user can log in or use the system.

By running "systemd-analyze critical-chain" in the command line, you can view the critical chain and see which units are delaying the system startup or causing bottlenecks.

The output of this command will display the list of units in the critical chain, showing the time each unit took to start (in milliseconds), the dependencies, and the final time at which the system becomes fully operational.

This information helps system administrators and users understand the startup process and identify any units that may be causing delays or issues.