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Comment: Re:Operating at 20W gives zero improvement. (Score 3, Interesting) 108

by serviscope_minor (#49125101) Attached to: AMD Unveils Carrizo APU With Excavator Core Architecture

Do you have a link for that? It's not that I disbelieve you, I strongly suspect that Intel would do that crap. I'd like to read more about it however if you hae a link handy, then stash the link for the next time this benchmark comes up.

Personally, I like the Phoronix Linux benchmarks. They're more meaningful for me since I use Linux and they're all based on GCC which is trustworthy.

The i7 4770 ocasionally blows away the FX8350 by a factor of 2, but in many benchmarks they're close, and Intel loses a fair fraction. The 4770 is the best overall performer, but not by all that much. It seems that the choice of CPU is fairly workload dependent.

For servers, I still prefer the supermicro 4s opteron boxes. 64 cores, 512G RAM, 1U. Nice.

Comment: Re:Mod Parent Up (Score 4, Informative) 71

I think this busts the physics, unless I misunderstand completely. Paging Dr. Shannon...


Think about baseband for a moment.

Let's say you hae a bandwidth of 100MHz.

You can basically change from 0v to 1v 100e6 times per second, giving 100Mbit/s.

But you can also introduce more symbols. If you have 10 voltage levels between 0 and 1 V you get 1Gbit /s.

What limits the number of symbols is noise. The datarate is symbol rate * bits per symbol. In the absence of noise, you can transmit an infinite amount of data in a 1Hz channel.

For non baseband signals, they generally use QAM to get symbols spanning the whole phase space around the centre frequency.

Comment: InGaAs? (Score 5, Interesting) 279

GaAs was the future of super-fast transistors. The Cray 3 was made from GaAs.

GaAs has a much higher electron mobility than silicon, 8,5000 versus about 1,500 for silicon. This allows for much faster switching. InGaAs has an electron mobility of 10,000 allowing even faster switching.

But that's just electrons which are used in P channel MOSFETs. For CMOS, you also need N channel MOSFETS. The kicker is that GaAs and InGaAs have respectively lower and much lower hole mobility so the N channel FETs switch rather slower than silicon.

CMOS is by far the only architecture. Historically it is the most power efficient since it only spends energy switching. On high speed, small scale CMOS, however, lots of power goes into the switching itself, the switching is fast enough that the devices don't really act very ideally and there's a lot of leakage.

Perhaps at very extreme ends, other architectures can compete, power wise.

Comment: Re:Pesticides for humans (Score 1) 224

by serviscope_minor (#49115559) Attached to: 100 Years of Chemical Weapons

After WWI, many chemists argued that there was no point making treaties against chemical weapons because you'd effectively have to outlaw the entire chemical industry... Chlorine gas & phosgene were both part of the dye industry.

Not only that but chlorine prodiction is utterly trivial: it might not be the cheapest way, but you can get it by electrolysis of brine.

Comment: Re:Smart men avoid marriage, period. (Score 1) 286

by serviscope_minor (#49109621) Attached to: An Evidence-Based Approach To Online Dating

Still, marriages can work as long as the man keeps the funds coming in, does whatever the wife tells him to, and sacrifices his sex life.
That's what it takes to "make it work" men!

The real problem is (of course), that if you have to "buy" a woman, then it's prostitution anyway, and she doesn't really love you.
So why bother with marriage at all?
Face it, if she really loved you, she'd stick with you without needing your money, or needing to be married. However, we all know how that works out :(

Works out fine for me. Sucks to be you, I guess. If you assume all women are massive raging assholes, and go through life as such, then you will never find one who isn't.

Comment: Re:Boring (Score 2) 286

by serviscope_minor (#49106447) Attached to: An Evidence-Based Approach To Online Dating

yep, women makes lists of features they want in a mate.

Technically 100% true, because so do men. If someone claims not to, they are almost certainly deluding themselves. However, your choice of ascribing a universal human trait only to women makes me susspicious that you have a strong "us versus them" attitude, and almost certainly a lot of misplaced ideas based on what all of womankind wants. That is of course doomed to failure since to a very good approximation there are no universal truthes about "all of women".

70%- 80% is about not only what they settle for but what they want since they want a lifelong project to change a man into their image.

Well, that's bullshit, in that it's not universally true. Unless of course you consider any compromise at all to fall under that.

100% perfect is too boring

No one's 100% perfect. If you try to wait for someone 100% perfect you will never find them.

Comment: Re:Linux was better when there was little funding. (Score 1) 95

by serviscope_minor (#49102195) Attached to: Linux Foundation: Bugs Can Be Made Shallow With Proper Funding

As Heinlein noted, TANSTAAFL, just like there's no such thing as free beer. Everything has a cost. Even free software.

Free software is free as in beer. If you claim it's not free because of the time to put in, then $100 lying on the pavement in front of you isn't free because you have to take the time t ogo and bend down and pick it up. Making such claims is basically changing the definition of the word "free" to mean something other than what it actually means.

Linux is Free as in Beer because you can get it for no cost.

And as for a free lunch, well, I think he was mistaken. I remember switching to Linux in the late 90s. For what I was doing, it was better in ever aspect than what I was switching from and free as in both speech and beer.

and the idea that "with enough eyes all bugs are shallow" is patently false.

It never meant there will be no bugs, it meant that once observed the bugs will be shallow and therefore fixed easily. Heartbleed is a perfect example of the many eyes thing: it was fixed within hours. Deep bugs are hard to fix, and shallow ones are easy to fix. The meaning of the quote was all about fixability, not nonexistence.

The solution would be to do a code freeze for 2-3 years while the developers of the various projects audit their code and the ways other projects interact with their code - not just for security problems, but to get rid of bloat and cruft. That's not going to happen, because it makes too much sense. Everyone wants the newest shiny.

If you want that, then OpenBSD is read and waiting for you :)

Comment: Re:Multi-value Mathematics? (Score 1) 210

by serviscope_minor (#49077887) Attached to: Interviews: Ask Stephen Wolfram a Question

Mathematics already has the concept of multi valued functions like square root, for example.

0/0 is undefined because you can reach literally any real number for 0/0 by taking a limit of a carefully selected function. For example, sin x/x winds up at 0/0 but has the value 1 at x=0. Now if you want 0/0 to equal some arbitrary number, multiply that expansion by the number and take the limit.

There are two major products that come out of Berkeley: LSD and UNIX. We don't believe this to be a coincidence. -- Jeremy S. Anderson