空間不足無法升級軟體 - jenhaoyang/backend_blog GitHub Wiki

Fixing this largely depends on where the cruft has built up.

Start with unnecessary packages and apt cache:

sudo apt autoremove && sudo apt autoclean
df -h

Use du to look for cruft in /var and /var/log.

sudo du -xh --max-depth=1 /var
sudo du -xh --max-depth=1 /var/log

If a lot of space is consumed by /var/log, I usually cleanup old log files with:

# Note, change +30 to the number of days you want to keep.
sudo find /var/log -mtime +30 -type f -delete

Other directories probably need to be handled differently.

Lastly, check if running processes have a lock on files pending deletion.

sudo lsof -nP | grep '(deleted)'
# If your system doesn't have lsof installed:
sudo apt install lsof 

If there are large files pending deletion, you may need to restart the process or daemon with the lock. 參考:
https://unix.stackexchange.com/a/578591