Links:
Wiki page URL: https://wiki.freebsd.org/BootTime
OS boot time comparison URL: https://www.daemonology.net/blog/2021-08-12-EC2-boot-time-benchmarking.html

Contact: Colin Percival <cperciva@FreeBSD.org>

Colin Percival is coordinating an effort to speed up the FreeBSD boot process. For benchmarking purposes, he is using an EC2 c5.xlarge instance as a reference platform and is measuring the time between when the virtual machine enters the EC2 "running" state and when it is possible to SSH into the instance.

This work started in 2017, leading to a conference presentation, "Profiling the FreeBSD kernel boot", and quickly yielded roughly 4850 ms of improvements (starting from a baseline of about 30 seconds).

Since June, another roughly 9790 ms of time has been shaved off the boot process, taking it down to approximately 15 seconds. There is still more work to be done; in particular, while the loader and kernel have been profiled, the TSLOG system Colin is using does not currently support userland profiling.

Issues are listed on the wiki page as they are identified; the wiki page also has instructions for performing profiling. Users are encouraged to profile the boot process on their own systems, in case they experience delays which don’t show up on the system Colin is using for testing.

This work is supported by Colin’s FreeBSD/EC2 Patreon.

Sponsor: https://www.patreon.com/cperciva