Anyone seen this? Snap fails to mount as /run fills up

[Martin Winter]

So I’ve noticed something unusual on my CI system (which 
installs/uninstalls debian packages and snap packages
all the time as part of testing):

I couldn’t install snap’s anymore - (only had the ubuntu-core loaded 
at this time)

dut:~# snap install --force-dangerous 
./frr_2.1-dev-20170207.191620-git.03bf19b_amd64.snap
error: cannot perform the following tasks:
- Mount snap "frr" (unset) ([start snap-frr-x1.mount] failed with exit 
status 1: Warning: snap-frr-x1.mount changed on disk. Run 'systemctl 
daemon-reload' to reload units.
A dependency job for snap-frr-x1.mount failed. See 'journalctl -xe' for 
details.)
root at ci-comp19-dut:~#

and looking at “journalctl -xe”

-- The start-up result is done.
Feb 07 06:26:18 ci-comp19-dut systemd-logind[1561]: New session 3160 of 
user root.
-- Subject: A new session 3160 has been created for user root
-- Defined-By: systemd
-- Support: http://lists.freedesktop.org/mailman/listinfo/systemd-devel
-- Documentation: 
http://www.freedesktop.org/wiki/Software/systemd/multiseat
-- 
-- A new session with the ID 3160 has been created for the user root.
-- 
-- The leading process of the session is 17387.
Feb 07 06:26:18 ci-comp19-dut systemd-logind[1561]: Failed to save user 
data /run/systemd/users/0: No space l
Feb 07 06:26:18 ci-comp19-dut systemd-udevd[17397]: failed to create db 
file '/run/udev/data/+cgroup:task_str
Feb 07 06:26:18 ci-comp19-dut systemd-udevd[17396]: failed to create db 
file '/run/udev/data/+cgroup:proc_ino
Feb 07 06:26:18 ci-comp19-dut systemd-udevd[17401]: failed to create db 
file '/run/udev/data/+cgroup:sighand_
Feb 07 06:26:18 ci-comp19-dut systemd-udevd[17402]: failed to create db 
file '/run/udev/data/+cgroup:signal_c
Feb 07 06:26:18 ci-comp19-dut systemd-udevd[17403]: failed to create db 
file '/run/udev/data/+cgroup:mm_struc
Feb 07 06:26:18 ci-comp19-dut systemd-udevd[17404]: failed to create db 
file '/run/udev/data/+cgroup:anon_vma
Feb 07 06:26:18 ci-comp19-dut systemd-udevd[17395]: failed to create db 
file '/run/udev/data/+cgroup:dentry(4
Feb 07 06:26:18 ci-comp19-dut systemd-udevd[17399]: failed to create db 
file '/run/udev/data/+cgroup:anon_vma
Feb 07 06:26:18 ci-comp19-dut systemd-udevd[17394]: failed to create db 
file '/run/udev/data/+cgroup:cred_jar
Feb 07 06:26:18 ci-comp19-dut systemd-udevd[17400]: failed to create db 
file '/run/udev/data/+cgroup:files_ca
Feb 07 06:26:18 ci-comp19-dut systemd-udevd[17397]: failed to create db 
file '/run/udev/data/+cgroup:pid(4365
Feb 07 06:26:18 ci-comp19-dut systemd-udevd[17403]: failed to create db 
file '/run/udev/data/+cgroup:kmalloc-

—> /run filesystem full!

dut:~# df
Filesystem     1K-blocks    Used Available Use% Mounted on
udev             1003440       0   1003440   0% /dev
tmpfs             204812  204812         0 100% /run
/dev/vda1        6060608 3362132   2367572  59% /
tmpfs            1024048       0   1024048   0% /dev/shm
tmpfs               5120       0      5120   0% /run/lock
tmpfs            1024048       0   1024048   0% /sys/fs/cgroup
/dev/loop0         78080   78080         0 100% /snap/ubuntu-core/1411
/dev/loop1         76800   76800         0 100% /snap/ubuntu-core/423
tmpfs             204812       0    204812   0% /run/user/0


These are my versions:
dut:~# snap --version
snap    2.21
snapd   2.21
series  16
ubuntu  16.04

Anyone seen this before? This is a basic Ubuntu 16.04 (server) install

After a reboot I don’t seem to have more space, so not sure if I 
should reconfig something to add more space to
/run or if this is some bug.

Thoughts?

- Martin Winter