Index ¦ Archives ¦ RSS

Userspace boot speed: less than a second

Estimated read time: 1 minutes

I did not care about boot speed for a long time, since servers usually restarted only for kernel upgrades, laptops suspend to ram all the time, and I have no desktop machine at home for years now. Though one use case started to motivate me recently: I use virtual machines a lot, and waiting for them to boot up is boring.

So I looked at the systemd-analyze blame output, and it turned out that for a base-only install the only service that takes a lot of time is netconfig. It’s because it was a oneshot service, so the whole boot process waited for dhcpcd to get an IP. A much better solution is to just start netconfig in the background and move on — and that’s exactly frugalwareutils in git does now.


$ systemd-analyze
Startup finished in 2030ms (kernel) + 1166ms (initrd) + 6755ms (userspace) = 9953ms


$ systemd-analyze
Startup finished in 2039ms (kernel) + 1146ms (initrd) + 892ms (userspace) = 4079ms
Again, this is for a virtual machine (where the host has some IO cache) and for a base-only install.

© Miklos Vajna. Built using Pelican. Theme by Giulio Fidente on github.