MMO hardware optimizations (Or lack thereof)

Because true parallel programming (as in utilizing multiple cores) is hard to do: most widely used computer programming languages are ill-suited for parallel programming and not every task is even suitable for parallelization. Programmers have to be extra careful when multiple threads access the same data and have to make sure there are access protocols in place when two cores want to work with the same data.

In most of these cases programmers serialize access in data with semaphores and mutexes. These in turn decrease the gain you get out of parallelization (someone has to wait and do nothing), and in some cases (with small data sets or global locks) may even incur a performance hit in comparison to a single-threaded application because of all the management overhead.

Debugging errors in such programs can be a real pain in the ass because of all the added complexity:
http://en.wikipedia.org/wiki/Dining_...ophers_problem

Most game engines process a relatively static data set (textures, geometry, UI) and do little to no heavy computation with that data (except object positioning and maybe inverse kinetics for animation, which may as well be static animations). There is also absolutely no gain in pre-computing additional frames, as most of the heavy lifting is already done on the GPU today.

Flipmode_sl said:

Yes and no. Games like EQ2 only cared about clock speed an thus never stressed more than 1 core of a multicore CPU and barely used any of my graphics card because their engine used the CPU to process shadows etc. Newer games like Rift and AoC made more use of the graphics cards but did t have sli support for a long time and didn't properly utilize multiple cores of a CPU.

Click to expand...

The EQ2 engine comes from a time where the developers still thought that more detailed models (as in more vertexes/polys) is the way of the the future, and (i believe) all model data on that engine had to go through the CPU. Advanced GPU features as geometry shaders or even dynamic tesselation were features unheard and undreamed of. Because there are diminishing returns on having ultra-detailed models (polygons that are rendered as 1 pixel or less on screen are just computational overhead), most modern graphic engines get that realistic rendering done with medium poly counts and detailed textures and complex shaders.

Also, MMO engines tend to be a somewhat different beast as single-player RPG engines: Because you can't reliably predict how many poeple are going to be on screen at any moment you can't really estimate how many GPU ressources can be spent on world and assets. Especially when your engine has to scale from a 5 year old computer (that wasn't even state of the art then) to next years ?ber-hardware.

The real kicker on MMO engines is that everyone wants to look really different from the next avatar, therefore the engine has to manage all those models and textures for weapons/armor/pets--and load and render them at the same time when you are somewhere in town where people like to show off their gear. MMO engine load estimation is done for those load peaks and not when you are alone in the world killing stuff.