I used to use mainline kernel 4.16.3, and most things worked fine. For testing purposes, I tried 4.16.9 by running
sudo dpkg -i linux-image-unsigned-4.16.9-041609-generic_4.16.9-041609.201805161024_amd64.deb linux-modules-4.16.9-041609-generic_4.16.9-041609.201805161024_amd64.deb. With this kernel, booting took really long (more than 2 minutes) and produced the following output: https://nopaste.xyz/?4b741a33276d0461#B3BbGFMFUIhZAjBGivihzmK5oUu/1DsxKlTEPxtnvp8=
apt-daily.service like recommended in Ubuntu 16.04 slow boot (apt-daily.service) did not change anything (but
systemd-analyze blame showed a similiar order, with
apt-daily.service on top.
Due to the syslog, I assume there is some snappy incompatibility. Is my installation of the kernel somehow wrong or may this be a bug?