Ars Technica's Hannibal on IBM's Cell

endersdouble writes "Ars Technica's Jon "Hannibal" Stokes, known for his many articles on CPU technology, has posted a new article on IBM's new Cell processor. This one is the first part of a series, and covers the processor's approach to caching and control logic. Good read."

Comments

Workstation?

[jericho4.0]

From this site and others..

" Last fall, IBM and Sony said they were developing a workstation based on Cell chips, which is the first product IBM will ship based on Cell."

Regardless if this is the first product shipped or not, a workstation is coming. I can't see it running anything but linux. Given the mass market targeting of the cell, I hope Sony makes a strong go at grabbing the market with cheap hardware, rather than trying to milk the high-end content creation market first.

More info in these slides

[Namarrgon]

Scroll down a bit here, there's some more tasty tidbits.

e.g. 234 M transistors (!) That's why I don't think this will be replacing the G5 any time soon. The die size (at the current prototype's 90nm) is over 200 mm2.

It'll have to get a fair bit smaller/cheaper before the PS3 can use it without major subsidies, and I don't know why they think general consumer devices will want it. God knows how much power it dissipates with all 8 SPEs clocking over at 4 GHz...

How do I code this thing??

[MagikSlinger]

The one thing I don't understand is how I would code for this thing. As best as I understand it, I now have some instructions for controlling the cache (or LAM, whatever) which sounds cool, but are there any details yet of how I'd write code for this? I'm also disappointed that the article didn't explain how one would use their SIMD instructions if they aren't using any of the existing standards. So I load my vectors with the cache control and ask the processors to ever so kindly add them?

Anybody out there with experience on this architecture or even attended the presentation itself can give us mere coders details? Preferably a website.

Re:How do I code this thing??

[fuzzbrain]

I don't have much experience or knowledge but there was an interesting article the other week about how the next revolution in programming languages will be a turn towards concurrency:

"Starting today, the performance lunch isn't free any more. Sure, there will continue to be generally applicable performance gains that everyone can pick up, thanks mainly to cache size improvements. But if you want your application to benefit from the continued exponential throughput advances in new processors, it will need to be a well-written concurrent (usually multithreaded) application. And that's easier said than done, because not all problems are inherently parallelizable and because concurrent programming is hard."

Obviously, it's not clear whether this is directly relevant to cell processors, but I think it's at least of passing interest. It's also worth considering whether concurrency-oriented languages like Erlang and Oz could become more important with these sorts of processors (not for games but possibly for scientific work).
See also the discussion of this article on Lambda.

Not useful for scientific computing

[renoX]

What I find interesting is that the vector processor are restricted to single precision floating point calculations.
This isn't terribly useful for scientific computations (there is the same problem with the GPU): currently the IEEE is working on a standard for 128bit precision floating point calculations!

Of course for 3D, video and sound, 32bit precision is good enough and *if* programmers (a big if) manage to overcome the pain of 'parallel programming' then it could be a big success.

Digital Rights Management

[wakejagr]

Another article on the Cell design at http://www.theregister.co.uk/2005/02/03/cell_analy sis_part_two/ seems to indicate that there is some sort of DRM built in.

The Cell is designed to make sure media, or third party programs, stay exactly where the owner of the media or program thinks they should stay. While most microprocessor designers agonize about how to make memory accesses as fast as possible, the Cell designers have erected several (four, we count) barriers to ensure memory accesses are as slow and cumbersome as possible - if need be.

Hannibal doesn't say anything about this (that I noticed) - anyone have more info?

Re:Digital Rights Management

[xenocide2]

Sounds like an enourmous misinterpretation of the concept of caching. As a multimedia programmer on the Cell, its likely you'll have sole jurisdiction over where stuff goes on your processor. Think of it like programmable cache management. Usually that's pretty stupid, because you want to write things back for longevity, but media is more transient--streams and whatnot. Barriers within that context would be cache levels.

But perhaps they've got some technical details (enough that they can count distinct features) that I can't find with a basic google search on the subject. It would certainly be out of Sony's previous style, though I understand they recently pulled their heads out of their collective asses and discovered that they were selling a loose metaphor of cars and crowbars at the same time, and came out with a public apology for sucking.

A proposal for Apple

[Anonymous Coward]

A proposal for Apple

I don't have an account, but this is an honest idea.

Why doesn't Apple include a Playstation 2 support card into their Macintosh line?

Problem: The OSX platform has almost no games. I own several macs, I love my macs, and I sincerely enjoy OSX. But it has no games, and that will never get better, especially as simpler games migrate to the web and the complex ones bail for the console market. The PC gaming market has essentially peaked.

Solution: Embed (or include as a BTO option) a PS2 chipset to a Macintosh. Run the generated display straight through to the graphical overlay plane. Done.

Everything works. The controllers are trivially converted to use USB. The DVD drive is already there. The display is already there. The USB and Firewire is already there. The harddrive is already there. The "memory cards" are already there.

Reason: The Macintosh game library explodes instantly to encompass something like 3,000 PS1 and PS2 games. With no need for emulation, the games are guaranteed to work out of the box and provide the Apple ease of use everyone loves. Sony increases their marketshare, Apple gets a viable expanding game library, and users get a vastly better gaming experience on OSX for maybe $40 of parts and engineering.

Why won't this work?

Re:Mistake

[TheNetAvenger]

A budget-class PC laptop of that time might have been about 900 MHz to 1.1 GHz. I wouldn't consider such a laptop anything near useable. They tended to have poor quality sound systems that bottlenecked the processor and atrociously short battery times. The ibook was legendary for its excellent battery performance

Get off what you 'assume', assumption is just intuition for idiots.

We have test 200mhz laptops with 80mb of ram 5gb hard drives, released 1997 all running WindowsXP Professional (yes even the themes turned on) and they benchmark faster than they did when they shipped with Windows 95.

Secondly, they can do full 30fps video as long as it is uncompressed AVI or even WMA 9. QuickTime (MPEG4), MPEG2, and real stutter horribly on video playback unfortunately.

As for battery, don't know, these laptops hold for 3hrs with a single charge, and yes techs are REQUIRED and have no problems using them daily in test scenarios.

Now if you really want to compare laptops to laptops, why don't I show you our 900mhz AMD Compaq laptops, they have JBL sound systems in them, and there isn't a single feature the cannot perform with the exception of running a T&L based video game, as the integrated video doesn't handle it, oh wait, the 900mhz PowerBook video didn't support such features either. (BTW, This is not to say that there are not several 900-1000mhz class laptops that have upper end video features), I am just using what we have in our test labs for comparison.

The 900mhz laptop has a DVD/CDRW, came out late 2000 early 2001 (trying to remember if we got them before holidays or not). They do full software DVD decoding with less than 20% CPU utilization and pretty much do anything fairly fast that we through at them. We even have a beta version of Windows 2003 server running on one with 256mb of RAM. (Yes we are always pushing the limits, but it works as fast as the WindowsXP pro version of the machine sitting next to it.)

Now off my rant... Macs truly are great, and the PowerBooks of the time were great, but that DOES NOT MEAN they were the BEST, WILL ALWAYS BE THE BEST, or you should be complacent listening to Apple tell you what you are getting is the best when it might not be. It is time for us as MAC users to stand up and DEMAND that technology becomes as much a part of what a MAC is as the EASE of USE in the Interface.

The time is now, we need to STOP accepting what they tell us and give us and force them to truly give us the LATEST technological concepts, not just the above average concepts when compared to the PC world. These are Macs, they SHOULD BE BETTER. IT shouldn't even be subjected to a debate they should be so far advanced a debate should not be possible. PERIOD.

Sadly, it just isn't true now, and has not been for many years. OSX has giving the Mac world some credibility backing OS technology, but not Apple needs to take Macs to the next level.

Even if my comment inspires one Mac user to say hey Apple, we want better, then maybe we all can be the symbolic person with the hammer from their 1984 video and WAKE THEM UP this time.