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Beer for the day: Bath Ales' "Wild Hare", an organic golden pale ale, with a calculated sharpness of hops, but not lacking the essential maltiness - here from wheat and barley - of a good ale. Ratebeer page here.

sockscatt pointed out this video of MIT's "Whiteboard", demonstrating a cart drawn on it; the program understands that the wheels will carry it down the slope, and animates the consequences.

If you ever heard The Firm's "Star Trekkin'", you'll remember it.. and here's the video (FLV download). Boldly going forwards, 'cause we can't find reverse

Or, for a classic bit of 80s synth: Visage - Fade to Grey (FLV).

And speaking of YouTube, you've probably noticed that it's been confirmed: Google's buying them for $1.65b in stock. No word yet as to whether the founders have called Mark Cuban to say "nyah nyah nya-nyaaah nyah".

Good Amiga interview here. But only five people working on OS5? That's not a large team for an application, let alone an OS; but, if they can pull a hare out of their hat, I'll be watching.

If you're within reach of Cardiff, Nov 19 sees a Doctor Who concert at the Millennium Stadium: "Composer Murray Gold and the Doctor Who team are working together with the BBC National Orchestra of Wales and the BBC National Chorus of Wales to stage the show. The star-studded concert, which will take place at the Wales Millennium Centre in Cardiff, will feature the BBC National Orchestra of Wales performing selections of Murray's celebrated incidental score, accompanied by a host of stunning visuals from Doctor Who.

The audience can also expect live appearances from some of The Doctor's greatest enemies including the Daleks and Cybermen. David Tennant has confirmed that he will be on hand to take part in a question and answer session alongside Russell T Davies and Murray Gold." (And four days later, the Scissor Sisters are in town =:)

shep_shepherd noticed Germany is being kept safe through vigilance: 'A large area near the town of Halle was cordoned off after a "flabby red, orange and green substance" was found by the road, Reuters reported. Fire officers in protective suits spent two hours inspecting the substance before concluding it was jelly.'

An interesting article on Archer Daniels Midland, one of the US' largest agricultural corporations, examining their recent promotion of ethanol as a fuel. (Coke lovers have them to thank for high fructose corn syrup, too)

So, Tower Records is/are history. They've been sold to a bidder that intends to liquidate the company, for $150m.

For the Bay Area folks: two CompUSA stores (3201 20th Ave, SF and 3149 Stevens Creek, SJ) are closing, with 30-60% off most stuff, and "at least 15%" off computers.

Word comes down from Studio Ghibli that Miyazaki himself is embarking on another project, for mid-2008 - but no other details have been revealed as yet. (His son is directing the studio's next release; they're not entirely in accord, with the father apparently expressing his artistic objections via another studio director)

Rather cool photo taken by deffox of lightning around wind turbines.

And sphelx noticed the quite wonderful auto bird turd emergency kit from Grumpy Girl.
 
 
 
 
 
 
Why the need for optimisation in the compiler?

Ah, that's an amusing tale in itself.

There's too much going on. Our software uses a fixed priority scheduler with a 25ms iteration. If a watchdog isn't serviced every 25ms, the unit is reset and execution begins again. Of course that means that if the code can't get it's execution done within 25ms, you have continuous reset.

RR were worried that the latest version of software wouldn't meet the 25ms deadline, so required -O2 optimisation to speed things up enough.

What I don't understand is why we don't just crank up the speed of the processor (which is rated for something like 4 times the speed it's running at).
Erk! Okay, that's just (Michael Bentine's) potty time. I suppose the processor would be rather warmer at that clock speed, but unless they're fast desktop devices, that's hardly going to be noticeable - even a PPC750fx at 300MHz runs barely warm to the touch, as the original iBook family showed well, lacking any fan at all. Anything ARM-based probably doesn't even know what a heatsink is.

25mS? Egad, that's an eternity! I decompressed entire 288x320 16bpp video frames in that time. Of course, I didn't need to execute in any specific amount of time, although it was quite simple to calculate the worst case (four soft-coded 8x8 subcells within each 16x16 block) - I designed the decoder to simply never take longer than 33ms per frame, allowing also for the other threads' overheads, such as grabbing data off the CD, and doling it out to the appropriate handler (video, audio, script, etc), but they were quite low impact operations, with most of the bulk work done by DMA, and with as little relocation of data as possible. An exceptionally fun project for what was, at the time, an exceptionally cool company.

Couldn't someone demonstrate it's impossible for the code to exceed its timeslot sans optimisation? Sounds as if they're imposing their guidelines, unable to accept that your code is indeed up to the task. Bad enough to interfere with a relatively modest development issue like compiler optimisation (where, of course, you're then having to trust the compiler to make the right decisions, as what is being executed isn't specifically what you wrote - fine in most situations, but not a decision I'd make for a mission critical system), but to force development into Ada? Certainly, I appreciate the theoretical considerations of the utility of strong typing, but still.. :-/
25ms, rather. Brain fart. Case is significant in many places, SI units most definitely included. ^_^
The processor is the Hi-Core processor, again in-house (it used to be the Lucas Aerospace Lae2000). But it's not much different to the '020 it replaces, except that it's on an ASIC. It'd certainly cope with the heat and electrical noise of bieng strapped to a Jet Engine even at 50Mhz (I think we use 25Mhz).

As for timing, that's one of the functions we do for verification, but it's hard enough proving that the formally built code meets its requirements (8 man months) without doing the same thing for an unoptimised build in parallel.

But, we do trust the complier. It's been certified for use on our product and our verification checks quite thoroughly that the complied code does what it should.

Oh, and it could've been worse. You could've said 25Ms. Which is about the length of human gestation.