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Comment: Re:One (Score 1) 107

The hotel with only wired in the room.

I keep a tiny wireless access point in my suitcase for these cases. Even with ethernet on my laptop, my phone and tablet don't have an RJ-45 connector and I don't always want to be using my laptop as an AP. Most hotel networks can't come close to saturating 802.11g, let alone .n.

Comment: Re:This is a response to RISC-V (Score 1) 46

by TheRaven64 (#49568857) Attached to: Imagination To Release Open MIPS Design To Academia

I'm moderately associated with RISC V (the lowRISC people are upstairs and I'm in the acknowledgements section of the RISC V spec). The main drawback of RISC V currently is the lack of software. Krste claims that the cost of the software ecosystem for RISC V will be around a billion dollars. My friends at ARM think that he's underestimated that by at least a factor of two. I had a student working on RISC V this year (using the BlueSpec in-order implementation) and the state of the LLVM toolchain is a joke - it's several man-years of work away from basic functional correctness (he had to fix a number of bugs to get simple benchmarks to work), getting it to be as performant as ARM (or even MIPS) is a lot further out.

MIPS ought to have a big advantage there, but they've squandered it. MIPSr6 is actually quite a nice ISA (I like it more than RISC V), but it is not backwards compatible with MIPS I-V or MIPSr1-5 (yes, those are different. Just go with it), so they lose all of their software ecosystem.

Comment: Re:AGP not working with SMP (Score 1) 223

by TheRaven64 (#49568765) Attached to: Linux 4.1 Bringing Many Changes, But No KDBUS
Sadly, both processors lost to the dust, in the end. Back around 2005, there were a lot of people who couldn't spell dual though, and 'duel processor' machines were going for about half what people were paying people who could spell for 'dual processor' machines on eBay. It was an object lesson in the financial value of learning to spell...

Comment: Re:This is a response to RISC-V (Score 1) 46

by TheRaven64 (#49567743) Attached to: Imagination To Release Open MIPS Design To Academia
lowRISC is cool, but it's not that useful for universities. For research (and teaching), FPGAs are much more useful because of the short turn-around. It takes me about 1-2 hours to go from making changes to our processor to finishing the boot of an OS on the FPGA and doesn't require anyone else's input (unless there are bugs, then some help is often useful!). The cycle for getting a chip fabbed is a much longer process, usually requiring a small team and a lot of money.

Comment: Re:It's marketting, not "open source". (Score 1) 46

by TheRaven64 (#49567731) Attached to: Imagination To Release Open MIPS Design To Academia
If you want a MIPS implementation that you can run in an FPGA, then we've built one and released it under an Apache-style license (not exactly the Apache license, because the Apache license says 'the software' in a lot of places). It's an implementation of a version of the (64-bit) MIPS ISA that is over 20 years old, so any relevant patents have expired. We've been using this in teaching for a couple of years (one exercise is to replace the branch predictor, for example). It's written in a high-level HDL, so more amenable to research and teaching uses, because the code is easy to make invasive changes to.

Comment: Re:OpenRISC (Score 2) 46

by TheRaven64 (#49567715) Attached to: Imagination To Release Open MIPS Design To Academia

It's not clear what version of the MIPS ISA they're implementing (the article I read just said MIPS32, which covers a whole range of things). It sounds like it's MIPS32r6, which is not backwards compatible with any previous MIPS version. The only value of MIPS over something like RISC V (which is increasingly the standard ISA for computer architecture research) is that there's a large body of existing software for it, so you can do real evaluation.

We've done a clean-room reimplementation of MIPS III (R4K compatible) implementation in BlueSpec, which is a high-level HDL. MIPS III and the R4K are over 20 years old, so any architecture-specific patents will have expired. In comparison, this core is only 32-bit (really not interesting for research) and is written in a low-level HDL (making the kind of invasive changes that you want to do in research difficult), and is an ISA that has very little software support.

Comment: Re:Z80 was in TRS-80 (Score 1) 118

by TheRaven64 (#49567627) Attached to: When Exxon Wanted To Be a Personal Computing Revolutionary

Any suggestions on that FPGA board?

We use the Terasic DE4 for most things, but it's insanely expensive - definitely only a board to use if someone else is paying. The SoCKit is quite nice - much cheaper and has a dual-core ARM board. We've ported FreeBSD to the ARM (adding devices for programming the FPGA) and our MIPS-compatible softcore to the FPGA, with virtio communicating between the two, which makes it easy to play with heterogeneous multicore. It's mainly intended for prototyping accelerator cores and there's a fast cache-coherent interconnect between the ARM cores and the FPGA so it's quite a nice platform to play with if you want to try and offload computation to the FPGA. It's a fairly small FPGA by modern standards, but still big enough for our CPU, which is a 6-stage in-order pipeline with caches, TLB, branch predictor and so on.

Comment: Re:What we are seeing is ... (Score 1) 337

by TheRaven64 (#49567583) Attached to: Google Insiders Talk About Why Google+ Failed
It wasn't like that when they started. For one thing, the ads were just how they made money, the search was their core business and they did change web search considerably. I also remember that Google ads were quite disruptive. They only accepted plain text adverts and they used the contents of the page to identify relevant ads. This meant that, unlike their competitors, their ads were both relevant (I'm looking at a page about X, therefore I'm probably interested in buying X) and non-obtrusive. Now they try to personalise the ads (just because I was interested in X last week doesn't mean that I'm interested in buying X now, sorry) and they have annoying video ads.

Comment: Re:Money (Score 1) 108

by AthanasiusKircher (#49567559) Attached to: New Privacy Threat: Automated Vehicle Occupancy Detection

In reality they just eat up a lane of traffic that could otherwise be used to alleviate rush hour congestion. It might be different if they actually ADDED HOV lanes instead of taking one of the normal lanes and rebranding it.

Uh, in many places they have done just that. I don't know how common it is, but I've been to a number of places in the US where the HOV lanes are even added as completely separate lanes from the rest of traffic, and I recall when one was constructed as such -- added into what was previously the wide median area of a highway.

After all, who's going to get into a car with a bunch of strangers, and not have a vehicle when they reach their destination?

I could be wrong here, but I believe the idea behind carpooling is typically you'd want people who have similar schedules to you, e.g., your coworkers. I've never had a particularly heavy traffic commute, but if I had a long commute particularly to a destinatation that was friendly to pedestrians and/or has decent public transport (e.g. many cities in the Northeast), I might consider an arrangement with a coworker if we lived somewhat near to each other. It may be less flexible than your own car every day, but it's cheaper, potentially faster, I only have to drive 50% of the time, and it's potentially much more flexible than alternatives (e.g. commuter rail) if I actually need a car sometimes or need a flexible schedule.

Comment: Re:Sucrose question (Score 1) 565

by AthanasiusKircher (#49565869) Attached to: Pepsi To Stop Using Aspartame

and sucrose into a "not great, but way better than anything artificial" category.

My question is: Is my paranoia scientifically justified?

When you imply that sucrose is not "artificial," then obviously what you say is not scientifically justified.

Sucrose doesn't occur naturally in significant quantities -- it needs to be extracted from cane or sugar beets. If you actually tried to eat the amount of sugar cane required to equal a can of Coke, you'd probably end up screwing up your bowel from excessive fiber intake.

The reality is most sugars occur in nature in contexts where they have significant amounts of fiber or other nutrients that affect how our bodies process them. Honey is one of the few exceptions, and its composition is basically equivalent (other than trace minerals) to something like high-fructose corn syrup. Just that last statement can cause you to question the arbitrary divisions in the "nature" vs. "artificial" idea.

Anyhow, to address your question directly -- there are limited scientific studies that show various downsides to artificial sweeteners compared to sucrose, though they do exist. But there are also plenty of studies that show better results for various populations consuming sweeteners instead of sucrose (mostly in terms of weight gain, diabetes, etc.). As for "corn syrup" (which I assume means "high-fructose corn syrup," rather than the mostly-glucose stuff used in candy-making), I'm aware of only 1 or 2 studies that seem to indicate some sort of negative effect compared to sucrose -- most studies find no difference or don't actually compare HFCS to sucrose directly.

For Europeans, the problem with the American diet regarding sweeteners mostly has to do with excess sweetener consumption everywhere -- hidden sugars in all sorts of processed foods, etc. Whether those sugars are sucrose or corn syrup or some sweetener is often irrelevant, because there are simply too much of them, and even when some calories are saved by sweeteners, they are often made up by excess other calories or bad things.

In sum, if we ate quantities of sweeteners or corn syrup that would replicate the amount of sweetness we'd experience naturally eating most "whole foods" in nature (fruits, vegetables, etc.), we'd probably be fine. But most people are addicted to the excess sweetness found in everything...

Comment: Re:danger vs taste (Score 1) 565

by AthanasiusKircher (#49565817) Attached to: Pepsi To Stop Using Aspartame

They probably just like diet soda (me, don't like the syrupy throat coating feeling of the regular stuff)


The whole discussion in this subthread seems to presuppose that everyone would obviously WANT to drink regular soda. But that's not a good assumption.

I rarely drink soda, but if I'm in a situation where it's the main drink being offered, I drink diet -- mainly because I can't stand the level of sweetness in normal soda. I've had many conversations with other people (both normal weight and obese) who feel the same way. "Regular" soda just tastes terrible to a lot of people, particularly if you don't like sweet things.

Diet soda also tastes really sweet, but somehow it's not as bad. AND you know that you're not ingesting hundreds of empty calories for a drink you detest.

I think it's what you're used to. I never grew up drinking a lot of soda. But I know people who grew up drinking loads of soda or syrupy iced tea, and they just love the stuff -- they think it's refreshing to have a cold Coke or iced tea loaded with multiple tablespoons of sugar per cup.

Me -- I can't stand the stuff. But once in a while, I do like the fizz in a drink. And since one can't typically order soda with a quarter of the normal sugar (which would be about the level I'd want), diet soda's really the only commonly available option.

Or, to put it another way, what is "worth the calories" to somebody? I don't like fast food -- most of it tastes horrible to me as well. If I want a burger, I want a REAL burger (I often grind my own meat fresh at home), not a processed calorie-bomb that has to have loads of sauce on it and flavor-enhancers to convince you to eat it.

Anyhow, to me it's "worth the calories" to have a homemade burger sometimes that might have the same calories as a Big Mac or whatever. To others, they might think it's "worth the calories" to eat the Big Mac, because they like the taste, but they might not like overly sweet sugary soda enough to make it "worth the calories."

Maybe there are some people out there who order diet soda even though they hate it, just to save calories. But I also bet there are a significant number of people who just don't really like regular soda that much. Frankly, I know very few adults beyond college age who do -- maybe it's just the people I hang out with, though.

Comment: Re: hmmm... (Score 1) 37

by AthanasiusKircher (#49565717) Attached to: An Open Ranking of Wikipedia Pages

an apatheist is someone who considers the question of the existence of gods as neither meaningful nor relevant to their life.

Although this neologism is suspect on etymological grounds, one could only hope that this word will become more popular and overtake the various misuses or imprecise uses of "agnosticism" for example.

For the record, "agnostic" (literally "lacking knowledge") in the traditional sense doesn't mean "I don't know" nor "I don't care," but rather is a positive philosophical belief that it is impossible to know for certain whether god(s) exist, e.g., because of the impossibility of collecting appropriate evidence or the nature of knowledge/deities/the universe/whatever.

Or, in terms of familiar statements:

"I believe" = theism
"I don't believe" = (strong) atheism
"I don't care" = apatheism
"I don't know" = weak atheism (aka "negative" or "soft" atheism)
"I can't know" or "No one knows" = agnosticism
"I don't know, and I don't care" = apatheistic atheism
"I don't give a crap, and nobody could ever know anyway" = strong agnostic apatheism


Comment: Re:How you drive (Score 1) 190

by AthanasiusKircher (#49565549) Attached to: The Engineer's Lament -- Prioritizing Car Safety Issues

rear-end collisions typically have a lot more to do with how others drive than how you drive.

Huh? What does that even mean?

If you said that collisions have to do more with "how other people drive than how **I** drive," maybe your statement would be logically comprehensible.

Or, to put it another way, for some values of "you", "others" = "you." (I.e. some people you (the parent) are including as "you" are part of the bad "others" who apparently are poor drivers.)

"Consequences, Schmonsequences, as long as I'm rich." -- Looney Tunes, Ali Baba Bunny (1957, Chuck Jones)