Accrding to this

Filesystem      Size  Used Avail Use% Mounted on
udev            713M     0  713M   0% /dev
tmpfs           149M   20M  129M  14% /run
/dev/vda1        48G   48G     0 100% /
tmpfs           743M     0  743M   0% /dev/shm
tmpfs           5.0M     0  5.0M   0% /run/lock
tmpfs           743M     0  743M   0% /sys/fs/cgroup
tmpfs           149M     0  149M   0% /run/user/0

It doesn't seem that you have problems in tmp. You don't have a /tmp partition after all.