Pemalite said:
fatslob-:O said:
Just so you know IPC isn't the whole story of performance. Oh and you appear to be right about jaguar (Got to check things out more often on my part.). I'm pretty sure floating point performance is a standard there are others like integer performance but that is not as important as the later.
|
IPC does matter, that's Instructions Per Clock, it's certainly more important than flops and is why AMD hasn't *really* been able to compete with Intel in the high-end, despite Intel having a core disadvantage.
The problem with multi-threading a game is that you have a primary thread, all your secondary threads have dependancies in the first, that's why generally you will always have a single thread that is more demanding than any others on a multi-core system when running a game, that's why a high IPC (A way to fixing it isn`t exactly a higher IPC but a higher clocks will do the trick because it will resolve dependencies alot better than a higher IPC.) at any given clock is important.
Floating Point as a gauge on performance really is pointless for games, note I said games.
If you were building an application that only used floating point, then it's an important measurement.
Game engines use allot of different types of math to achieve a certain result, the problem is you nor I will ever know what type of math is being used at any one instance in a games scene. (You do realize why we went away from integer math in the first place, right ? Here I'll give you the answer on my behalf and that's because using integers to calculate transformations and lightings was too slow initially and it became especially prevalent in the 3D graphics era. Alot of processors those days didn't feature an fpu and instead to render in 3D precisely they had to use software enabled floating point math.)
Take the Cell for example, it's a single-precision iterative refinement floating point monster, my CPU isn't even as fast in real-world tests when it comes to that, however the Cell's integer and double precisions floating point performance is orders of magnitude slower than my 3930K or even Jaguar, yet, overall in a real-world gaming situation, both CPU's would pummel the Cell.
|
@Bold
There are other factors to performance such as clock speeds too. If both processors can output the same amount of instructions at the same amount of time then I would prefer if the procressor has the higher clock because not only does it match the processor with a higher IPC but it has a higher clock`s to overcome sequential workloads too. Remeber how a single core clocked at 3 Ghz will beat a dual core that does 1.5 Ghz. Well the same situation applies here because there are certain programs that won`t be able to leverage a higher IPC but instead a higher clock provided that the each line of code is dependent on the last line of code. (I did not say that IPC did not matter but you have to account orther things too about the processor.)
Yet these games use alot of floating point math from what I am seeing. (Even if games were to use integer it`d be miniscule alot of times and you know this.)
The cell had alot more in common with what you'd call a vector processor. The actual processor was the PPE as for the SPE's they were a bunch of SIMD units, nothing more plus their instruction sets were pretty narrow.
