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Cell Architecture Explained
IdiotOnMyLeft writes "OSNews features an article written by Nicholas Blachford about the new processor developed by IBM and Sony for their Playstation 3 console. The article goes deep inside the Cell architecture and describes why it is a revolutionary step forwards in technology and until now, the most serious threat to x86. '5 dual core Opterons directly connected via HyperTransport should be able to achieve a similar level of performance in stream processing - as a single Cell. The PlayStation 3 is expected to have have 4 Cells.'"
Or does the logical extension of this chart:
t ributed.gif
http://www.blachford.info/computer/Cells/Cell_Dis
Make it look a little more like a HAL than a Cell?
Since the main goal of the chip is to pump through graphics, regardless of what device its in, a GPU is better grounds for comparison.
From TFA: "Existing GPUs can provide massive processing power when programmed properly, the difference is the Cell will be cheaper and several times faster."
Its supposed to do 250GFlops when? 2 years from now? Apparently the Geforce 6800 Ultra will do 40GFlops and thats today.... extrapolate with some doubling here and there it seems a lot more reasonable.
So the big thing is that it comes down to programming. It came up a few times in the article "Doing this will make it faster but will make for one hell of a time for the programmers" It may have a huge potential but may take a while to get everything efficiently as Sony would like. Reminds me of when the GF3 first came out and was beaten by the GF2U in some tests. IIRC it took a while for games to come out that took advantage of its programability. It'll be interesting to see how well the programmers can fair between now and Cell's release.
There are several assumptions that lead to tremendous theoretical performance figures. The simple fact is that like the Itanium, the Cell processor depends on some rather complicated software that will solve issues like parallelism, coherency etc. The article clearly states that the Cell architecture is a combination of software and hardware (1st page). This is good because performance can always increase (via a better OS or microcode) but it is also bad because it means that initial versions may not stand up to their performance claims.
;-)
Also, let's not forget that developers will be unable to keep up, unless some highly sophisticated libraries and languages are made available. I really don't expect the majority of developers to be able to cope with massive parallelism from the beggining (not just 2x SMP or hyperthreading, this needs a totally different mindset).
To sum this up: the hardware will deliver, but the software is a critical unknown in the equation. I have faith in IBM
P.
No, this sort of architecture is a general trend towards paralellization. It is smart, and it is known to work, and I would expect some bright Sparc wise people to chime in and say "u-huh" and some SGI wise people to chime in and say "I've seen some of this before." The OS people are starting to move things in this direction, and I've heard that Darwin has had the asynchronous messaging type threading model for a while (RTFA: the article explicitly mentions Tiger's GPU leveraging techniques). If you have the head for it, try reading up on NUMA and compare that with SMP.
The math is simple. CPUs are CPUs, and anyone can make one that is the same speed as the competition, and if they do it second they can do it cheaper. The guy that can make 20 CPUs work like one CPU that does 20 times the work in a given time will win because he can always just throw more hardware at the problem. The SMP guys have to go back to the drawing board. In this case, the only way to beat-em is to join-em. Maybe doing the specific "Cell" computing design isn't it, but the ol' PC is dead. If these things start hitting the commodity price-points.
That's a big, fat IF. So, don't bet on it (yet), but it's even worse to ignore it.
--- Nothing clever here: move along now...
Because IBM is an R&D and service company mostly, or it looks like they are headed that direction eventually. They can make better profit margins by just designing then licensing out the tech. By concentrating on their core missions they can maximise ROI, and leave the headaches and drudge work of mass production and marketing of consumer level stuff to some other company, and still get paid well for it. Granted, you get a higher gross income with being the manufacturer, but you get a better net income by just licensing and developing.
At least it looks that way to me, and it's following their past business model of selling off consumer level production, like they did with hard drive manufacture to Hitachi. Whether that will be a very long term smooth move I have no idea, but in the short term it's actually making them money. Profit margins at low end retail are small, they want no part of that, too clunky for them. Fabbing the chips is a different story, they need to be able to have a place to build what they R & D, so in that sense its logical for them to do that,and get that aspect subsidised by licensing and direct sales (saves them research costs long run) but after that point it's just manufacturing vacuum cleaners or blenders, they don't want to, and that's all PCs are now, just another consumer appliance.