Yesterday, I noticed a couple of problems with the resident computers:
- The server's CPU usage was around 198% (it's a dual-core system), dominated by java, zfs-fuse, and ksoftirqd. Exiting jedit fixed this; launching jedit (either as root or as myself) caused it to resume.
- On the workstation, libreoffice (with KDE integration) couldn't handle file "open" or "save as" operations: the file-chooser dialogs would come up blank, and remain so - I didn't wait more'n a mnute to see if this was a permanent hang or just an exceedingly slow operation. Removing KDE integration (and killing off the demon) made it work again, albeit with the not-so-nice default UI.
Turns out: both problems were caused by a power outage Friday morning (from 07:37:45 to 07:37:55 apparently; I was out walkies at the time).
The server and workstation are both on a UPS.
The old workstation isn't. Nor is the lab NAS gadget. So, when the power blinked off, they went down and remained so pending manual intervention.
The old workstation still (when it's turned on) exports an occasionally-used filesystem via NFS. The server and the new workstation both mount it.
Having an NFS server drop off the air while the filesystem is mounted elsewhere leads to interesting problems at the elsewhere end, even if nobody is overtly trying to access it.
Come to think of it, I've been encountering problems like this since the 1990s.
Guess I should look into modern alternatives to NFS, In My Copious Free Time.
Also, as long as the old workstation is powered off anyway, I suppose I might as well reconnect the fireproof USB drive and the big inkjet printer to the new server, which, unlike the old server, ought to handle them adequately. Anyway, keeping the old workstation on when we're well past heating season is just wasteful.