A Look At The Speedy Clear Linux Boot Time Versus Ubuntu 19.10
The systemd-reported boot time was compared between the latest Clear Linux and Ubuntu 19.10 daily images. Ubuntu 19.10 was used for offering the bleeding-edge packages and being more in line to what is offered by the rolling-release Clear Linux. As well, Canonical has been working on some boot time improvements for Ubuntu 19.10.
An Intel Core i9 9900K and AMD Ryzen 9 3900X systems were used for comparing the Ubuntu 19.10 vs. Clear Linux boot performance with having two distinct systems to look at for their boot times.
The kernel portion of the boot time on the Core i9 9900K system went from 1.5 seconds on Ubuntu 19.10 to 901 ms on Clear Linux. The AMD Zen 2 desktop's boot performance didn't change all that much from 2.9s on Ubuntu 19.10 to 2.7s on Clear Linux. (Keep in mind there is different hardware in the two boxes for testing two distinct systems for comparing Clear Linux vs. Ubuntu 19.10 and not looking at Ryzen 9 3900X vs. Core i9 9900K as not being the focus of this comparison.)
Clear Linux does keep its boot-loader out of the way in the boot process leading to much shorter times than Ubuntu (and other distros for that matter).
Where Clear Linux really shortens up the boot time is for the user-space portion. On both Ubuntu 19.10 and Clear Linux it was a measure to hitting the GDM log-in screen with auto-logins not being enabled in one or the other by default.
When looking at the total boot time, it was 15.9 seconds reported by systemd on Ubuntu 19.10 while just 1.5 seconds on Clear Linux for the Core i9 9900K box. On the Ryzen 9 box it went from 11 seconds on Ubuntu to 4 seconds on Clear Linux.
More boot time results in our next Linux distribution comparison. You can see how your system compares with phoronix-test-suite benchmark systemd-boot-total.