Comment by okso

The four steps that take time when booting a Linux system are:

* bios/UEFI

* bootloader (GRUB/...)

* Linux kernel

* service management

bios/UEFI often have settings to reduce the time waiting for user input. Same goes for the bootloader.

You can use `dmesg --boot` to analyze the boot of the Linux kernel.

You can use `systemd-analyze critical-chain` to find out about what slows down the start of the services.