OK, so the changes didn't fix both problems. Someone has reported the dreaded error condition being shown again. I've fixed the message (it wasnt scheduled maintenance at all) and made it log all the database activities when this error is thrown. Its safe to say that it is NOT because the machine is running out of steam, the machine itself is bored out of its tiny processor most of the time and rarely records a loadavg of over 0.5 (and still copes quite well with 10 times that load). So, something is going wrong inside the database and I intend to determine what it is!
Anyway, in theory, a small change I have made should enable things to improve, but we shall see... Either way, the extra error logging will help me, hopefully, get to the bottom of it sooner.
Apologies to anyone who see's the Database Error page!
Steve.