Death of a hard drive
Now, I don't know what *all* that means, but I do know "sda" and "Unrecovered read error" in the same entry aren't generally what you want to see.
smartctl -t long /dev/sda ran, and smartctl -a /dev/sda said that while there were some errors, the drive was OK.
I'm not chancing it, and have resurrected (read restarted) my backup strategy. You do have a backup strategy too, don't you?
I'm expecting the drive to fail (no doubt at the most inconvenient time?), and have had a look at hybrid SSD drives. They seem to provide about 90% the performance of a full SSD drive, but for 25% of the cost.
Update: 2011-09-23
I got annoyed with the constant 15 second slowdowns, I ordered the Seagate 500GB Momentus XT 2.5" Hybrid SSD. Then I thought I'd have a look at what sector it was that was causing the problem, and hey presto - it was the same one all the time.
I wanted to find out what the problem file was, so I ran:find / -type f -exec cp {} /dev/null \; >/dev/null Eventually, it showed the problem as an I/O error on
/home/calum/.mozilla/firefox/qrtsapqll.default/places.sqlite.
I backed up (why isn't it backuped?) my bookmarks, and removed the file.
Bingo, no more problems. I'll run a new smartctl long test on it, and see what it thinks.
Problem fixed (for now), and new drive coming soon.