Consider dpkg --force-unsafe-io

[Colin Watson]

lpcraft can be slow (how slow exactly?) when installing lots of packages from a PPA as part of job setup. We should consider dropping in a file /etc/dpkg/dpkg.conf.d/force-unsafe-io containing the text "force-unsafe-io", which would tell dpkg to trade off filesystem robustness in favour of performance; in the context of lpcraft we don't particularly care about filesystem robustness in the event of a system crash, since one can always just retry the lpcraft run instead.

[Colin Watson (cjwatson)]

Haw added a launchpad-buildd task, but this isn't in fact a problem that needs to be fixed in launchpad-buildd: the images built by livecd-rootfs that launchpad-buildd runs all its builds inside all already contain /etc/apt/apt.conf.d/99buildd files that set `--force-unsafe-io`. It's only the inner container used by lpcraft that's an issue here, and launchpad-buildd has nothing to say about that.

[Haw Loeung (hloeung)]

Ah, thanks for the explanation Colin.

[Colin Watson (cjwatson)]

In fact, I've just noticed that the same file is present in the LXD images used by lpcraft as well, so we already end up passing `--force-unsafe-io` to dpkg. This is therefore not a bug.