Bug#803531: systemd: timeout mounting /home (btrfs) at boot

[Brian May]

Package: systemd
Version: 215-17+deb8u2
Severity: important

When my computer boots, it times out trying to mount /dev/sdc1 to /home.
That is it takes more then 90 seconds.

Yet when I run "mount -a" by hand it takes a maximum of 2 seconds.

If I keep rebooting the computer by hand, eventually it works, and it is
fast.

Wish I knew what systemd was doing when it says it is mounting the
filesystem that is taking all that time. I don't know how to debug this
however.