IBM Power servers most reliable in new survey

the results seem pretty much as expected except for maybe Debian. I'm very surprised they had such a low downtime especially as compared to the more cutting edge Ubuntu although it could be more a factor of people using it on a "roll your own" server which may not be of the quality of the big vendors. I'm curious where Red Hat fits in as they weren't mentioned. Overall however with these reliability numbers are very good for all operating systems. What I'd really be curious about however is how they compare in planned downtime? For maintenance, patches and the like. While planned downtime is certainly better than unplanned, I'd rather have 2-4 hours unplanned downtime if it drastically cut the unplanned downtime (assuming both instances affected productivity..doing upgrades when no one is in the building to notice wouldn't count)

I wondered, too, how much of the downtime was for patches and how much for "other."

For a server, especially, it would seem to be a balancing act regarding how often to patch to both minimize downtime and maintain security.

Most packages don't require a reboot and wouldn't affect downtime. I imagine that kernel patches are the culprit ...