We explain how to analyze the performance of system boot with Systemd and its syntax in general.
What is Systemd-analyze?
This command is responsible for analyzing and debugging the system administrator in multiple Linux distributions.
Using Systemd-analyze in Linux
Its use is simple; for example, if we want to obtain general information about the starting time of the operating system, we must execute the following command:
This should be executed without any argument, thus listing information about the total time it takes to start each service, including the time spent by the kernel, initrd and user space during startup:
If we wish to get a list of all the units in execution, ordered by the time they take to initialize, in descending order, the blame subcommand is used to access this information; we will execute the following;
We can see in this information that each unit is ordered based on the time spent; this is practical for management tasks since it was simple to find out which service takes more time to start and analyze the problem specifically about it.
If the objective is to see a tree associated with the critical time chain for a fixed objective or a list of specific units, we must use the critical-chain parameter in the following way:
If you want to obtain information about a particular service, we must execute the following syntax:
systemd-analyze critical-chain “name”.service
To see data from a remote host through the ssh protocol, we must use the -H flag and indicate the directive user@host as well.
systemd-analyze blame -H [email protected] systemd-analyze critical-chain -H [email protected]
To see systemd-analyze options, we can use the following commands:
Thus, we have seen how to implement and use systemd-analyze in the Linux distributions and in this way take much more direct control over the boot of this.