Why Sony should also use a Cell Processor for PS5 (x86+Cell coprocessor)

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captain carot said:

DevilRising said:
The Cell processor was a pain to develop for, and not a single developer ever really used "all of that power" to the max. So why would they go back?

Actually devs used 'all the CELL's power'. But in multiple ways it was way weaker than many people think. And where it actually was strong it still was hard to get the ideal workload.

 

The two biggest problems here are (in a simplified way):
Clock doesn't matter, except you compare the same architecture. Today's slowest Pentium Dual Core is lightyears ahead of the fastest Pentium 4 Dual Core, the latter one having way higher clock.

FLOPS don't matter, except you compare the same architecture. Like Pemalite showed with that Radeon 5K vs. Radeon 7K example or with current GeForce vs. Radeon GPU's and yes, even with different CPU's.

 

That cloth simularion example people show over and over again is one of the benchmalrs that scale extremely well with floating point performance and parallelization. It's just a benchmark though. And very specific one too.

With the old Xbox One API you can see a massive hit in GPU based simulation. RAM bandwidth, cache and yes, those ACE's might be not totally unimportant here as well. The Asynchronous Compute Engines again are something that people heavily misunderstand though.

Long story short, CELL is outdated. As is the concept of Sonys Emption Engine, which actually was a great concept at the time of development yet already outdated a year after release.

The Emotion Engine had the same architecture as did PSX and N64. It was already outdated before PS2 was released, but Sony chose an architecture that the developers were already familiar with (technically so did everyone else; Dreamcast had the same architecture with Saturn, Gamecube shared an architecture with Power Macs and Xbox had a Celeron inside).

Yeah, the problem, as you point out, with the Cell is optimising the workload; if you don't do it, the processor isn't going to perform well.

Errorist76 said:

torok said:
At this point, it's a ridiculously outdated and underpowered CPU. Your slides just show it loses to a netbook-level CPU at 1.6 Ghz. It has zero advantages. Those 30 bucks could be used in a better CPU.

Its only advantage was the SPEs, but the modern usage of GPGPU neglects that. What is the use for 6 SPEs when you have thousands of cores in a GPU? Even your slides are showing that offloading these tasks to the GPU resulted in massive gains. If you compare the Cell with the X360 processor (slides), it's just a 3X speedup. For GPGPU standard that is beyond pathetic. I'm not even going to start with the nightmare of working with a x86 CPU, a GPU, an extra RISC core, and 8 SPUs.

The Cell was an incredibly stupid idea, based on the assumption that it was intelligent to perform GPU-oriented tasks on the CPU. In the end, the GPUs are way more massively parallel and the Cell can't provide decent speedups to compensate its cost. If you consider the terrible dev tools for the SPEs, compared with the great toolkits for GPUs, plus the change in mindset to work with this aberration, it is simply not worth it.

To make things even worse, Cell is also based on the PPC architecture, that is dying a slow death due to lack of research while x86 advances in a quick pace. The smaller scale also implies on larger costs. There is no point in pouring money on researching a new Cell while you can just use existing CPUs and GPUs to do the job better.

About the CPU being a bottleneck while memory was the previous bottleneck, here is the thing: any computer will have a bottleneck. If we magically replaced the Jaguar with a Threadripper, the bottleneck would be the GPU. Throw in a 1070, and now it's RAM. More RAM? Well, the GPU would be the bottleneck again. It's a never ending game.

Ridiculously outdated but still beating Jaguar CPUs at floating point calculations.

That's because the Jaguar can do so much more. If it was only about floating point units, everyone would be using nothing but GPU's, because this is what they're good at. And the way GPU's work, is roughly how the Cell works as well. And it's pretty much outdated, because it is not being further developed anymore.