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Comment Re:Hardware acceleration (Score 1) 129

You're going to be in for a rude surprise.

OpenGL drivers on Windows are awful, DirectX is where all of the development effort goes on driver teams. At work we wrote our app using OpenGL for a 3D overlay because we ship on Windows, Mac, and Linux, but on Windows we took the time to write a DirectX backend instead of OpenGL and the stability and performance shot up noticably. OpenGL is a forgotten "checkbox feature" on Windows today, not much more.

Comment Re:A solution: system codecs. (Score 1) 640

Why not use system codecs? Because you're not solving the original problem. The problem was dependency on externally variable code that was frequently proprietary to render the web. Instead of requiring Flash to view websites in a default web browser, now we'll require K-Lite Codec Pack Max Extreme 2.0++?

Which codec would you use? Theora isn't implemented on most systems. h264 won't work on Windows by default (7 will, but that's just a small portion of the market). VC-1 won't work on Mac and Linux. MPEG-2 isn't even guaranteed to be found.'ve just opened a whole 'nother can of worms.

Comment Re:Opera (Score 1) 505

That's not true at all. Firefox, since 2.0, has had memory caching just like Opera does. Go to about:config and tweak how much is used (which is default-set based on your system capacity, just like Opera). It's called "browser.cache.memory.capacity".

Comment Re:RTFA (Score 1) 242

I understand why they don't agree with the practice, but this is hardly front-page Slashdot news. The summary is, if anything, very misleading. This has NOTHING to do with Mozilla's plans for HTML5 or web openness, it's everything to do with some nameless blogger disagreeing with another nameless blogger's implementation of video fallback.

This is non-news, to say the least.

Comment Somebody help me on this (Score 2, Insightful) 242

Some random Mozilla Hacks (note the word Hacks) blogger posts some code that web developers can use to implement HTML5 video (which does not use javascript, contrary to the implications in this article and summary?) and also provide a fallback path for non-HTML5 Video browsers (IE, Opera, etc). Their particular method of providing the fallback code uses javascript to determine browser capability, and uses Flash if HTML5 Video is not there.

Why is this upsetting to anyone? The implication from the summary is this is a less "open" way to do it, but last I checked Javascript/ECMAScript is a standard that all browsers implement already.

I cannot fathom why anyone would be so upset by some blogger providing JS-implemented video fallback implementations.

Comment Re:Hmm, really? (Score 1) 155

By definition, a superscalar processor does not need to be instruction re-ordering, speculative execution, or branch prediction. All a superscalar processor needs to do to be called superscalar is to dispatch more than one instruction per clock cycle to redundant functional units on the processor -- the 360's CPU is absolutely superscalar.

Incidentally, you are incorrect other aspects anyway: the Xenon cores DO have branch prediction, just in a significantly diminished capacity compared to what we're used to on the PC (small history tables, simpler logic, etc). The Cell's SPEs have none at all, and rely on "branch hints" instead where the programmer or compiler specifies which path may be likely at any given point. As a result, it also has speculative execution.

But you are correct in that the 360's CPUs -- like the Cell's PPU and SPEs -- is in-order and thus does not re-order instructions. It is up to the compilers to generate optimally ordered instructions, which isn't as big a deal as you may think on a closed-box system with optimized compilers. Back in '03-'04 I worked in IBM's compiler group on this very thing.

Comment Re:a few facts please? (Score 3, Informative) 155

While it certainly sounds like you know what you're talking about, it's pretty clear to anyone with a game-dev background you do not.

Cell's SPEs are actually PRIMARILY used as aids to graphics processing (T&L) by most developers. Look into how games like Heavenly Sword use the SPEs as part of its "faux" HDR or games like Killzone 2 use SPEs to implement deferred rendering for awesome smoke effects. The SPEs are, in PRACTICAL TERMS to PS3 game developers, very essential to the 3D rendering side of the console.

While RSX is "powerful enough" to do its own T&L, it cannot compare to the standalone power of the 360's Xenos chip. There are many reasons for this (6 fixed vertex shaders on RSX vs the unified shaders on the 360 which permit far higher vertex workloads, to the RSX's limited bandwidth vs the 360's eDRAM bandwidth, to triangle setup rates). On the PS3, developers need to leverage Cell in intelligent ways to draw comparable graphics to the 360. If an intelligent and determined PS3 developer really leverages Cell, it can make unparalleled graphic in the console world. The problem is, it costs a fortune in time and money to do it and very few developers can. It's simply not worth it to even attempt it for most developers.

As a sidenote, Cell is not at all good for most game AI for many reasons (not the least of which is the lack of branch predictors in the SPEs).

Additionally, people keep making the mistake of assuming the PPU in the Cell is basically the same as each core in the 360's CPU. That's not at all true. There are some significant differences, including native Direct3D format support in the 360's CPU to the new VMX128 vector units (which have 128 registers per context per core [6 total], vs 32 on the PPU) as well as additional instructions specifically tailored towards 3D games (like single-cycle dot-product instructions). The combined triple VMX-128 units on the 360 are still faster than most quad-core Core i7 in vector processing, so I'm perplexed by the notion that it's somewhat slow or underpowered from what I've read from some people.

If you're truly interested in how PS3 games use Cell, check out the Beyond3D community where PS3 developers post in detail about how they do what they do. And Cell is a major factor in 3D rendering on the PS3. It has to be.

Operating Systems

FreeBSD 7.0 Bests Linux In SMP Performance 288

cecom writes "After major improvements in SMP support in FreeBSD 7.0, benchmarks show it performing 15% better than the latest Linux kernels (PDF, see slides 17 to 19) on 8 CPUs under PostgreSQL and MySQL. While a couple of benchmarks are not conclusive evidence, it can be assumed that FreeBSD will once again be a serious performance contender. Some posters on LWN have noted that the level of Linux performance could be related to the Completely Fair Scheduler, which was merged into the 2.6.23 Linux kernel." Update: 03/06 21:32 GMT by KD : An anonymous reader sent in word that Linux kernel developer Nick Piggin reran the benchmark today and came to a different conclusion: In his benchmark Linux was faster than FreeBSD.

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