Unleashing the Power of the Cell Broadband Engine

An anonymous reader writes "IBM DeveloperWorks is running a paper from the MPR Fall Processor Forum 2005 explores programming models for the Cell Broadband Engine (CBE) Processor, from the simple to the progressively more advanced. With nine cores on a single die, programming for the CBE is like programming for no processor you've ever met before."

Comments

Wow ...

[JMZorko]

... all those _registers_ make me salivate! One of the coolest things about the RCA1802 (the processor I learned on) compared to others in its' time was that it had _loads_ of registers when compared to a 6502 or 8085. It spoiled me, though ... when I started exploring those other CPUs, I always thought "Huh? Where are all of the registers?"

So yes, I want a Cell-based devkit now, 'cuz this sounds like _fun_ :-)

Regards,

John

Re:PS3 Suggestion

[rpdillon]

Every PS3 hard drive is shipping with Linux onboard.

Reminds me of programming the nCube

[Animats]

The nCube, in the 1980s, was much like this. 64 to 1024 processors, each with 128KB and a link to neighboring processors, plus an underpowered control machine (an Intel 286, surprisingly.)

The Cell machines are about equally painful to program, but because they're cheaper, they have more potential applications than the nCube did. Cell phone sites, multichannel audio and video processing, and similar easily-parallelized stream-type tasks fit well with the cell model. It's not yet clear what else does.

Recognize that the cell architecture is inherently less useful than a shared-memory multiprocessor. It's an attempt to get some reasonable fraction of the performance of an N-way shared memory multiprocessor without the expensive caches and interconnects needed to make that work. It's not yet clear if this is a price/performance win for general purpose computing. Historically, architectures like this have been more trouble than they're worth. But if Sony fields a few hundred million of them, putting up with the pain is cost-justified.

It's still not clear if the cell approach does much for graphics. The PS3 is apparently going to have a relatively conventional nVidia part bolted on to do the back end of the graphics pipeline.

I'm glad that I don't have to write a distributed physics engine for this thing.

they gave up...

[YesIAmAScript]

Both Sony and MS realized they couldn't make a single true general-purpose CPU with the performance they wanted for a price they could afford to sell in their consoles.

Sony went to a CPU, GPU and 7 co-processors (Cell).
MS went to a 3 CPUs with vector-assist and a GPU.

Both companies are going to need to spend a lot of time and money on developer tools to help their developers more easily take advantage of their oddball hardware, or else they will end up right where Saturn did.

I guess the good news for both companies is that there is no alternative (like PS1 was to Saturn) which is straightforward and thus more attractive.

PS2 requires programming a specialized CPU with localized memory (the Emotion Engine) and it seems to get by okay. So developers can adapty, given sufficient financial advange to doing so.