This is a peak maintenance downtime r/ffxiv post. I am sorry in advance.
Every time we experience an extended (say, 24-hour long) maintenance, there's a bunch of QQing about how people want an extra day added to their service accounts and how unacceptable the amount of maintenance downtime there is in FFXIV.
Well, ya girl did the math.
I went through every lodestone maintenance post and pulled them all - there are maintenances that only affect one world, or one data center, in addition to those that impact every world (referred to as "All Worlds Maintenance"). I created a data set dating back to the release of 3.0 that contains each maintenance, what it was for, whom it affected, and the duration of the maintenance (taking into account that many end early). One last thing to note: I assumed when the lodestone post said the server would be down "for a few minutes" that meant 15 minutes. /shrug
Since June 18, 2015 (that's roughly 2 years, 7 months, and 11 days), All Worlds have experienced 29,185 minutes of downtime. That's around 486.5 hours total.
That means around 2% of the total time between June 18th, 2015 and now has been spent with the game servers undergoing some maintenance that every single player, regardless of data center or world, will experience.
In addition to maintenance that affected All Worlds, certain Data Centers needed specific attention as well, resulting in an additional server downtime of (in minutes):
Aether Primal Chaos Mana Elemental Gaia
1,664 1,654 890 490 310 250
and last but not least, the following Worlds can't actually play nice and needed their own specific maintenance:
World Maint. Time (min) World Maint. Time (min) World Maint. Time (min)
Anima 40 Exodus 30 Odin 15
Asura 35 Fenrir 30 Ramuh 30
Atmos 30 Garuda 35 Shinryu 10
Balmung 15 Hades 15 Shiva 30
Belias 120 Jenova 120 Tonberry 35
Chocobo 65 Mandragora 40 Valefor 180
Valefor baby what is u doin
You could get an idea of how much maintenance you speicifcally have experienced by adding the base number of minutes + your data center's minutes + any sever specific minutes if you cared.
This (you will want to open that in a new window) is a visualization of those minutes by month, in a sort of timeline. The peak in May 2017 is due to the 47-hour maintenance (!!) that closed all the servers while SE migrated the North American Data Centers to a new physical location.
Using this graph, we can see that July 2016, for example, was pretty quiet as far as maintenance goes. Unless of course you were on Aether or Primal, then you had a lot more downtime.
I got curious so I compared the All Worlds maintenance that accompanied the first few months of 3.0 with the first few months of 4.0. Here is that timeline. They are pretty comparable, with the exception of a lengthy maintenance due to the Chaos Data Center being moved.
Here's how the numbers compare:
Heavensward 3.0-3.2 Maintenance Stormblood 4.0-4.2 Maintenance*
10,090 minutes 8,035 minutes
168 hrs 134 hrs
*Includes today's 24-hour maintenance.
Even if we exclude the outlier of the Chaos DC move, there was still 1,530 more minutes of maintenance between 3.0-3.2 then there was from 4.0-4.2. That's 25.5 hours of downtime difference between the release of Heavensward and the release of Stormblood! Progress!
Some other random statistics:
I found info for 140 cases of maintenance downtime.
55% of the maintenance instances were completed earlier then the end time (77 of them).
~2% ended later then the end time (3 of them).
8.5% of the maintenance didn't actually result in an inability to log into the server - they were things like maintenance on party finder (1 example), those times during SB launch when they had to take down the Ruby Sea, or when fishing in La Noscea crashed Aether so they closed those zones.
SE identified 44% (62 of my 140 sample) of the maintenance as "Emergency".
FFXIV devs love starting maintenance at 10-11 PM Pacific Time. 42% of those maintenance samples began during those times.
Major patches are all 24 hours, with the exception of 3. 3.1 was only 23 hours (lol), 3.2 was 9.5 hours, and 4.1 was 6.
If you want the lowest amount of downtime, based on this trend, play on a Gaia DC server, and maybe avoid Jenova.
Here is a google sheet with what I put together if you want to get feisty and do something yourself. Make a copy. :>