[PS3] #27: Wachten....Wachten....Wachten... ;(

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Op vrijdag 14 april 2006 15:11 schreef P-Style het volgende:

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Grapjas.

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Op vrijdag 14 april 2006 15:25 schreef P-Style het volgende:

en de kans op een GTA is ook redelijk groot.

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Op vrijdag 14 april 2006 15:36 schreef SocialDisorder het volgende:
Hey onderschat het commerciele succes van Table Tennis niet!

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Op vrijdag 14 april 2006 15:46 schreef Diablos79 het volgende:

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De xbox360 krijgt exclusief Ping Pong van Rockstar de PS3 krijgt GTA exclusief

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New PS3 operating system details?

The site Playstation 3 Portal recently got hold of a few details of the PS3's OS, and how it will make use of the Cell hardware. Technically, these details qualify as "rumor," but for the reasons given below I think they're pretty plausible. First, the details:

As was witnessed in their demonstrations at GDC, Sony is planning to have an Operating System running constantly in the background, just like one witnesses when using the Xbox 360 OS (aka Dashboard). They plan to have a "Blade" like pane that can appear out of the right hand side of the screen for viewing and participating in activities that the OS enables.

This include but are not limited to,

- Multi-User Voice Chat across all games, even outside of the games own UI
- Multi-User Video Chat across all games, even outside of the games own UI
- Notifications and messaging to be sent between users regardless of the games they are playing

Like the Xbox 360, these come at a cost and our sources have told us that these features use approximately:

- 64mb of the 256mb of available XDR memory off the Cell CPU
- 32mb of the 256mb of available GDDR3 memory off the RSX chip
- 1 SPE of 7 constantly reserved
- 1 SPE of 7 able to be "taken" by the OS at a moments notice (games have to give it up if requested)

As PS3 Portal report points out, it has long been public knowledge that the PS3 will reserve one SPE for use by the OS. We've also known that at least part of the function of this reserved SPE was security- and DRM-related. Each SPE's local store can be walled off from the rest of the system for trusted access by only authorized threads. Thus the SPE is ideally suited for security and DRM-related purposes.

I had taken it as a given that, with one SPE being constantly reserved for the OS in a kind of "Big Brother" capacity, the reserved SPE would host at least one continuously running OS thread, and that the OS would have a trusted region of memory walled off from the game code. So the new news here would be the features hosted by the OS concurrent to the game, the amounts of each memory type reserved for the OS, and the fact that a second SPE can be commandeered by the system if additional processing power is needed. Based on what we already know of the PS3 and how Sony intends to use it, I find all three of these items to be plausible.

Big online plans, and the reserved SPE

There was a thread on Beyond3D some time ago about the PS3 OS's reserved SPE, and what it would be used for. The consensus was that the SPE, in spite of its lack of dynamic branch prediction, would be more than sufficient for most normal, low-level OS duties. Note that you're not gonna run Vista or OS X on an SPE, but something along the lines of a very slimmed-down embedded OS with minimal functionality is feasible, especially when you consider that game code will be dominating the vast majority of the hardware and the user experience. In fact, there was some question as to what such an OS would be doing with all that leftover horsepower.

I think the answer is probably to be found in the interactive, real-time, user- and network-facing sides of the console's functionality. This includes not only the audio/video chat and IM referenced in the PS3 Portal rumor, but also the aforementioned DRM (for streaming and downloadable online content that might be dynamically integrated into the game experience) and security/privacy-related code.

Regarding all of these items, take a look at the following quote from an early Cell white paper by IBM:

From the beginning, it was envisioned that the Cell processor should be designed to provide the best possible experience to the human user and the best possible response to the network. ...We anticipated that most devices in which the Cell processor would be used would be connected to the (broadband) Internet. At an early stage we envisioned blends of the content (real or virtual) as presented by the Internet and content from traditional game play and entertainment. Being responsive to the Internet means not only that the processor should be optimized for handling communication-oriented workloads; it also implies that the processor should be responsive to the types of workloads presented by the Internet. ...With the opportunities for sharing data and computation power come the concerns of security, digital rights management, and privacy.

This white paper was one of the first to be released on Cell, and it clearly indicates that PS3 was designed from the ground up as a node on the network. It also suggests, well before anything was known about Playstation World other than a name, some of the scope of Sony's online ambitions: real-time communications, DRM-protected audio and video, the dynamic integration of online-only content into gameplay, and more.

Not only is all of this enough work for one SPE, but in some circumstances it may be enough work for two SPEs. And for what it's worth, I also think that the reserved memory numbers given are fairly reasonable, as well.

In sum, the performance of PS3's network-facing functionality is going to be limited by network latency and bandwidth, where latencies are counted in milliseconds. This being the case, the SPE's distance from main memory, lack of dynamic branch prediction, and steep branch penalty aren't going to be a killer if it's primarily tasked with processing this kind of traffic while a game runs on the rest of the Cell.

Impact on performance

One thing I want to clear up from the report, before this little tidbit makes its way into the fanboi flamewars, is the following statement:

In the case of the PS3 this equates to 12.5% of the available Cores on the CPU always reserved, an additional 12.5% sometimes taken by the OS, 12.5% of the available RSX memory and 25% of XDR Cell memory. Balancing these out, one could argue that Sony has removed up to 25% of the available CPU power and 18.75% of RAM for these features as well as others that are not mentioned here or will be added in future updates to the PS3 Operation System.

Let's say you're right-handed, and I tie your right hand behind your back. Are you now missing "50 percent of your manual dexterity"? Are you missing "25% of the use of your appendages (= fingers + toes)"? How about if I tie up your left hand instead?

My point here is that PS3 games, at least initially, are not going to use all five or six available SPEs (remember, of the eight SPEs, one is disabled for yield purposes, a second is reserved for the system, and a third allegedly can be taken over by the system if it's needed). And when games do get around to using all the available SPE power, they won't be using all of it in the same way. Some SPEs will do some types of things, and some will do some others. If one SPE gets taken out of play by the OS, its work will shift to another SPE; the impact that this will have on any one game depends on what task that SPE was running and how the task was rescheduled.

So the idea that Sony's removal of two SPEs can reasonably be characterized as a 25 percent reduction in CPU horsepower is nonsense. The performance impact all depends first on how many SPEs each game uses, and then on what the workload mix is like, and finally on how the work gets redistributed by the game when that extra SPE goes offline. In short, there's no way to give an easy answer to the question of the kind of impact this will have on game performance in general.

Update: There's a claim in a newer Beyond3D thread that I'd missed to the effect that Sony is not considering having the OS periodically demand a second SPE. This was the most surprising of the claims in the article anyway, so I won't be shocked if it doesn't hold up. We'll keep you posted.

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Op maandag 17 april 2006 23:57 schreef SocialDisorder het volgende:
Sony heeft wel een ideale plek op de E3 bemachtigd;
[afbeelding]

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Op dinsdag 18 april 2006 08:30 schreef SocialDisorder het volgende:

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Jawel, andere hal. Maar aangezien dit het PS3-topic was, vond ik de noodzaak niet aanwezig om Microsofts plekje te posten.

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Op dinsdag 18 april 2006 10:25 schreef SocialDisorder het volgende:

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Ik dacht dat het toch wel redelijk bekend is dat het LA Convention Centre 3 hallen heeft.