Interesting post from WoW general forum.

[Lissa]

You go to explain how bugs/problems are introduced when you make changes to a system, in response to a quote which contained "assuming no core system changes are needed."

How much do you understand about programming? From the sounds of it, very little. Just writing some code can cause problems with the core when you are not even trying to effect the core. Bugs occur in ways that don't make sense because a bug is a logic error, and humans are not 100% logical when they code. As such, when trying to add more value to a program, it is quite possible to introduce a new bug that effects the core program when you don't even try to effect the core program, that is the way things are.

Irrelevant. What is being discussed is whether or not these servers can eventually operate smoothly with little need for babysitting. That has absolutely nothing to do with how complex the system is. How complex the system is relates to how long it takes and how hard it is to make it smooth, not to the possibility.

And as I have said, Clusters are far more different beasts than a standard server. If you had ever built one or worked on one you would know this. As something becomes more complex you have to watch it more carefully which does require more expenditures in resources to make sure the system is functioning correctly. Thus you will be able to sit back and just not bother with the system as minor fluctuations in the system can have dire consequences due to the complexity and you can never just walk away from a system like this as those minor fluctuations can have ripple effects that could eventually bring down the system. These types of systems need constant survilance to make sure that they will not go down.

Of course natural disasters like tornadoes change things, but they'll destroy any system anyway, and are kind of out of scope.

By the way, I'm getting the feeling of an implication that normal servers/PCs aren't complex, which is absurd. Perhaps you might want to learn assembly, or maybe even delve into hardware design.
I was under the impression that these servers ran on silicon chips.
[right][snapback]71110[/snapback][/right]

No, you do not understand. PC and server are complex, but clusters, servers working in concert to increase uptime and fault tolerance are like monkey to a human. Both the monkey and human are complex, but the human has even more complexity to it, thus the same thing with clusters to stand alone servers. There is far more going on between clustered servers than there is between a server and clients connecting to it. Again, if you had ever worked with a cluster, you would understand quite well what I am talking about.