
Distributed systems for fun and profit (2013) - lelf
http://book.mixu.net/distsys/single-page.html
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nulltype
Distributed and highly available systems are pretty interesting but something
I've noticed is that it's really surprising how much you can get done with a
centralized system (say a single redis instance) and how much easier it is.
Some of the cloud VMs can run for years with only transient issues (GCE live
migration is neat).

High availability is really cool as well, but I recently learned that world of
Warcraft has apparently had <97% uptime for years due to weekly maintenance.
That leads me to reconsider just how necessary those additional nines are. It
seems like a lot of services would be better off optimizing for, say,
operational efficiency than uptime. Doing server upgrades and rolling out
patches when you have a multi hour maintenance window sounds waaay easier than
live updates to your servers.

Of course it depends entirely on the service you are running, but I'm still
impressed that a service as large as world of Warcraft can work fine with that
level of uptime.

~~~
jamesblonde
97% is not impressive. Nine nine's reliability is - like Ericsson's AXD301,
built using Erlang:
[http://stackoverflow.com/questions/8426897/erlangs-99-999999...](http://stackoverflow.com/questions/8426897/erlangs-99-9999999-nine-
nines-reliability)

~~~
zodiac
I think nulltype's point is that yes, 97% is considered "low reliability" by
software engineers, but Blizzard and the WoW players don't seem to mind this
low reliability.

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makmanalp
I've been reading this, and I think it's a great intro to the subject that
isn't inscrutable and doesn't go into excessive detail. I also like:
[http://christophermeiklejohn.com/distributed/systems/2013/07...](http://christophermeiklejohn.com/distributed/systems/2013/07/12/readings-
in-distributed-systems.html) as a source for more in depth readings in
specific subjects. Many of these are seminal papers

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buckbova
[http://nil.csail.mit.edu/6.824/2015/schedule.html](http://nil.csail.mit.edu/6.824/2015/schedule.html)

Someone posted this last time I asked about distributed systems.

