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Comment: Re:the school already is lying (Score 4, Interesting) 364

by slyfox (#31223054) Attached to: PA School Defends Web-Cam Spying As Security Measure, Denies Misuse

A student has been quoted as saying:

"Frequently, the green lights next to our iSight webcams will turn on. The school district claims that this is just a glitch. We are all doubting this now."


The lawsuit filed in court states:

"[The student] was at home using a school issued laptop that was neither reported lost nor stolen when his image was captured by Defendants without his or his parents' permission and while he was at home."


If this is true, sounds pretty damning to me.


+ - Intel Larrabee die shot and release dates 1

Submitted by Vigile
Vigile (99919) writes "The details of Intel's CPU/GPU hybrid project known as Larrabee have been slowly leaking out over the past 12 months including news that it was based on older x86 cores, that rasterization was a primary focus and that it would use a vector-extended x86 ISA. Now we have our first detailed look at a Larrabee die that shows a 32-core design that could reach as high as a 2.5 TFlops based on clock speed predictions. The move to a 2010 release schedule has also been confirmed by Intel as it seems they are still struggling to see similar levels of efficiency to GPUs from NVIDIA and AMD."

Comment: Re:As a Developer the Question I Have Is ... (Score 1) 300

by slyfox (#27888959) Attached to: New Firefox Project Could Mean Multi-Processor Support

We do need something to make multiple-CPU programming easier though. Threaded programming in C/C++ or similar can turn into a nightmare real quick, it's error prone and complicated.

If you want to use C++, I suggest Thread Building Blocks, which is an open-source C++ library. It is a set of reasonable primitives, including a task scheduler and some simple parallel iterators that create tasks. The task scheduling makes it mostly independent of the specific number of cores in the system, which is key. It think it is part of most Linux distributions these days. For simple data parallel computations, you can avoid thinking about threads and locks entirely, but yet it also allows provides the low-level primitives to write sophisticated highly optimized code, too.

P.S. I totally agree that Erlang is just *not* the right solution for multicore. Erlang's message passing is great for the application for which it was designed (telecommunications equipment with multiple independent line cards and such) or any such highly concurrent applications with high availability needs. It just isn't well suited for multicore programming (which just has an entirely different set of challenges such as data locality).

Comment: Re:What? (Score 5, Informative) 420

by slyfox (#26772785) Attached to: Nvidia Is Trying To Make an x86 Chip

No, the above post really overstates what goes on inside today's x86 chips.

It is true that Intel and AMD internally break up x86 into simpler "micro-ops" to simplify the internals of the chip. However, the specific micro-ops uses are tailored explicitly for x86 instructions, and many match up with x86 instructions one-to-one. The mapping really isn't that programmable, either. Most of the mapping is hard-coded and highly optimized. It would not be trivial to support another ISA such as PowerPC, even for just user-mode instructions. If you then consider all the privileged instructions, virtual memory, and virtualization stuff, you have a real mess. It would likely be easier to start from scratch rather than try to retrofit a current x86 to be anything other than an x86. Sure, you could reuse some of the arithmetic units and memory controllers perhaps, but the core would have to change pretty dramatically.

That said, Transmeta (RIP) did have technology that would likely make it easier to run non-x86 code on its processor, and the translation was done in software. But even its internal instructions were likely closely match to specifics of the x86 ISA.

Comment: Re:Next stop, infomercial and/or MLM (Score 1) 674

by slyfox (#25178551) Attached to: Simple Device Claimed To Boost Fuel Efficiency By Up To 20%

Even as recently as 2002 you could buy a 44mpg highway Civic. No, not a hybrid - it was the "HX" model with lean-burn engine.

The EPA recently changed the way they measure fuel efficiency (MPG). With the new standard: "the city mpg estimates for the manufacturers of most vehicles will drop by about 12 percent on average, and by as much as 30 percent for some vehicles. The highway mpg estimates will drop on average by about 8 percent, and by as much as 25 percent for some vehicles", according to the EPA web site. This follows an early revision (also downward) in the 1980s.

In addition, Hybrids have the most benefit on stop-and-go city miles, but less impact on highway miles. Hybrids typically have other features that help, such as continuously variable transmissions and smaller and efficient engines.

This isn't some sort of conspiracy. Car manufactures are making the cars people want to buy. For those looking for fuel efficiency, something like the Prius really does reflect state-of-the-art fuel efficiency.

"Ada is the work of an architect, not a computer scientist." - Jean Icbiah, inventor of Ada, weenie