I used to work at a place that had gigantic computer systems (even a Cray XMP) and maintainence was done by the 3rd shift on Monday mornings. I doubt they have a 3rd shift but Monday morning in down-under-land would be Sunday morning and afternoon here I believe so the maintainence idea has legs.
Ben
Most (online) gaming companies do their maintenance on tuesdays or thursdays...
That said, avoiding the days when there's nothing else to play might be a good idea.
Codemasters do their maintenance between about 9am and 1pm (GMT/BST) each tuesday, which avoids bothering people that are normally at work.
WoW on the other hand can afford to hire additional staff, and their maintenance is usually 4am to 7am (PST for US servers, GMT for european) every tuesday.
EVE takes a more forceful approach and performs maintenance every day at noon to 1pm GMT. The game being unavailable for an hour a day isn't too bad once you get used to it.
The idea of 'prevantative' maintenance (ie, reboot of the servers, vacuum (yes, that IS a technical term) the databases etc) isn't a bad one at all. Given the current reliability of the servers rebooting them on friday to at least reduce the risk of them crashing over the weekend would be a start.
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