The VM I run my IRC bot in ran out of disk space today. Usually I use baobab (similar to the delicious SpaceMonger on Windows) to quickly find whatever offending 30GB log file or temp file is responsible. But this time, I couldn't see any large files. I already have a cronjob to automatically run zeopack on my bot's ZODB database file every night (otherwise it grows and grows), so it wasn't that.
df -h was showing that out of the 36GB available on the VM's disk, 100% was being used. But baobab showed that the space in use by the / filesystem (in other words, everything) was a mere 4.9GB. I was stumped by this for at least an hour until I found this in the documentation:
Disk Usage Analyzer will not count the /proc dir, nor any file size that is not related to a "plain" file, so symlinks, character blocks, device blocks will not be part of the directory size.As I read the bit about /proc, it dawned on me that when I first built my server, I set Terminal's scrollback lines to "Unlimited":The machine had been on for months, and the three or four open terminals I had open were collectively hoarding over 30 gigabytes of scrollback.Welp.