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User Journal

Journal Journal: Improve your posts and end world hunger 4

Someone just sent me the best link I've seen in a long time: http://freerice.com/index.php.

It's a simple vocabulary game which asks you to pick the closest synonym for a word from four options. It shows you adverts, and for every word you get right they donate 10 grains of rice to the UN World Food Program. It adjusts the difficulty based on how many you've got right so far, up to a maximum of 50. I seem to be hovering around he 40±2 mark at the moment.

EDIT: I got to 47 for a bit, but then dropped down again. Still haven't made it to 48, which they claim few people beat.

Unix

Journal Journal: Decrypting the OpenBSD Theme Song 5

OpenBSD has just released the theme song for the 4.2 release. The song title is 100001 1010101. What does that mean?

Converting them to decimal, we get:

100001 = 32 + 1 = 33
1010101 = 64 + 16 + 4 + 1 = 85

As ASCII codes, these are ! and U. Not particularly meaningful, but it gives us a hint. Considering the song's subject some connection to money could be a good guess. Considering OpenBSD's focus on cryptography, it seems like it might be encrypted in some way, but presumably some way that's known to be insecure enough that someone with only two characters and a knowledge of the context can decrypt it. A Caesar Cypher is an obvious bet. Since it's in binary, a power of two seems like a nice bet for an easy-to-guess key. We want one that leaves both characters in the letters region of the character set (65-90, 97-122). Picking 32, we get:

1000001 = 64 + 1 = 65
1110101 = 64 + 32 + 16 + 4 + 1 = 117

This corresponds to the letters A and u. Since Au is the chemical element for gold, this is probably the answer.

Of course, with only a two-letter cyphertext and no knowledge of the algorithm or key, we can't be sure, and the 'real' decryption could be anything, but it seems likely that the correct answer is gold considering the subject of the song. Assuming it is a Caesar Cypher, we know that the distance between the two characters must be 52, so we can write a simple program that will output them all:

#include <stdio.h>

int main(void)
{
for(int i=0 ; i<128 ; i++)
{
printf("%d: %c%c\n", i - 33, (char)i, (char)(i + 52) & 127);
}
return 0;
}

The only results where both are in the letter range are:

32: Au
33: Bv
34: Cw
35: Dx
36: Ey
37: Fz

Of these, only Au is an atomic symbol. The others might have some other meaning, but Au still seems like the best bet. No other powers of two give us a value in the letter range, although 16 gives 1e, which might mean something to someone (decimal 30? ASCII code for record separator?).

In summary, the title for the new OpenBSD theme song could be anything, but is probably Gold. Also, I am definitely a geek.

User Journal

Journal Journal: Squash Ball: 1, Eye: 0 2

I recently started playing squash. It's quite fun, you put two people in a small room and they try to hit a small ball past each other. It turns out, this ball is almost exactly the same size as an eyeball. It also turns out to be somewhat more resilient than an eyeball. When I played last Thursday, the ball left my opponent's racket and went straight into my right eye.

This, perhaps unsurprisingly, way quite astonishingly painful. After about five minutes, my vision started to go cloudy, so I went to the hospital. One of the nice things about Swansea is that there is a hospital right next to the sports centre, which specialises in eyes. After waiting for a little while, someone shined a bright light in my eyes, poked them a bit, and gave me some drops to take. Apparently my iris was bleeding (hence the cloudy vision). I had to use two kinds of eye drops and go back the next day. By this time, it was hoped, the cloudiness would have cleared enough for the doctor to see into my eye and see if my retina had detached.

The next day, the cloudiness hadn't cleared much, but the doctor couldn't see any damage (but I have to go back after another three weeks to make absolutely sure).

Today, for the first time since the accident, I can see clearly. Unfortunately, the pupil on my right eye is still very dilated (I think this is the eye drops, but I'm not completely sure), and so I am having to wear sunglasses and sit in a dark room to avoid being dazzled. The good news is that the week-long moratorium on exercise is lifted tomorrow, so I can go to salsa in the evening.

Intel

Journal Journal: Intel Adds Vertex Shader Hardware Support

According to El Reg, Intel have added hardware vertex shader support to a number of their GPUs. Those affected by the driver update include the Q963, G965, 945G and the mobile GM965. Previously these parts only supported pixel shaders in hardware, and used a (slow) pure-software implementation for vertex shading. The hardware contains a mixture of fixed-function and programmable hardware; this driver update will use the programmable hardware to run vertex shaders.

The new drivers are Windows-only, but the existence of this functionality provides some hope that their Free Software drivers will also gain vertex shader support at some point.

Graphics

Journal Journal: Is 3D Hardware still Hard?

First generation video cards were basically a blob of memory and a DAC. Then came simple 3D cards that were basically rasterisers. Then the cards started doing transform, clipping, and lighting calculation all in hardware. Then manufacturers started moving away from the whole fixed-function concept. Modern graphics cards are basically floating point vector stream processors.

While the Open Graphics Project is aiming to build a fairly simple fixed-function device, I wonder if this is the best approach. It seems that it would be simpler to start with something like the OpenRISC core and:

  1. Remove the integer units (not needed).
  2. Increase the floating point pipeline width to 128 or 256 bits, giving 4-way SIMD on every operation.
  3. Add hardware support for trig operations.
  4. Stamp a few dozen of these cores onto a die.
  5. Do everything else in software.

You'd get a chip that is heavily optimised for doing graphical operations, but still a general purpose design, a lot like modern GPUs. The other benefit is that there are a lot more open source developers capable of writing software OpenGL implementations for this kind of device than there are able to make meaningful contributions to GPU design.

For bonus points, you could add a few stock OpenRISC cores, a memory controller, USB controller, etc to the design, and have a completely open source system-on-a-chip design.

User Journal

Journal Journal: DRM-Free iTunes 3

Apple launches a DRM-free version of iTunes, and the Slashdot coverage is an article bitching that it adds your name, email address, and date of purchase in the metadata.

The rest of the world seems to be having a slightly more positive reaction, judging by how badly lamped the iTunes store was when I tried checking it last night (song previews were failing to load, individual pages took thirty seconds or more, and the two albums I upgraded last night are still downloading).

Album upgrades cost 25% of the original price, which isn't too bad for doubling the quality and ditching the DRM. I'd bough 12 albums from iTMS (including one EP) before the DRM started irritating me by being incompatible with devices I wanted to use to play back music. Of those, only two were available DRM-free.

I plan on buying a few albums DRM-free in the next week or so. I hope other people will too, so that Apple can point at the proportion of DRM-free downloads and say to the other labels 'look how much money you are losing by not selling your tracks DRM-free.' Then all they need to do is get the price down to EmuSic levels (or, at least, the same price they have in the US, for those of us in the UK).

User Journal

Journal Journal: Hosting Resolved

I had another chat with my hosting company's CEO today, and he agreed to give me one of their standard plans for slightly less than it usually costs with twice as much bandwidth and a second IP. While this is still a bit more than some other companies, knowing that if stuff goes wrong I have email and IM addresses for the CEO, CTO and head tech and can bitch at them until someone fixes it probably makes it worth while. They extended my existing contract by a month to give me time to shop around for a new host, and then agreed to the suggestion I felt fair after I'd looked at some of their competitors.

Mac Mini Colo are now back on my 'would recommend' list. Anyone looking for hosting that falls somewhere between low end dedicated servers and high-end virtual private servers would do well to check them out.

In a year, I will probably move to a Xen-based solution, but at the moment they tend not to have enough RAM or disk space. Anyone looking at starting a hosting business should take note of this. There is a serious shortage of VPS solutions with decent amounts of disk space and RAM. Get some 750GB disks (maybe RAID-1, two per machine), and 5-6GB of RAM, and you can put 10 VMs with decent specs in each node. CPU is rarely the limiting factor for budget hosting, and live migration can help out a lot here if you choose to go for a SAN backend and just have a lot of disks somewhere in your rack.

Networking

Journal Journal: Anyone know of a cheap dedicated hosting company? 2

My current hosting company wants to put their prices up. I currently have a Mac Mini running OpenBSD colocated with them. I am looking to move, and have the following minimum needs:
  • 1GHz CPU,
  • 512MB of RAM,
  • 1IP,
  • 50GB/month of transfer,
  • OpenBSD or FreeBSD.

I am flexible in terms of storage space; I currently have an 80GB disk, but I'm using less than 5GB of it. I'd like to start using a bit more, but not having more bandwidth makes this difficult.

Can anyone recommend a hosting company that would offer this kind of set-up for under about $50/month? DedicatedNow seemed like they had a reasonable offer, but they had some quite unreasonable demands, such as needing a copy of my passport faxed to them to complete the transaction (and I don't do that for any business, particularly not one I have had no prior dealings with).

In unrelated news, it looks like I'm getting a Google-sponsored minion for the summer. The SoC results were announced this morning, and the project I am mentoring got accepted. Should be fun.

Education

Journal Journal: If We Taught English the Way We Teach Mathematics

Imagine that your only contact with "English" as a subject was through classes in school. Suppose that those classes, from elementary school right through to high school, amounted to nothing more than reading dictionaries, getting drilled in spelling and formal grammatical construction, and memorizing vast vocabulary lists -- you never read a novel, nor a poem; never had contact with anything beyond the pedantic complexity of English spelling and formal grammar, and precise definitions for an endless array of words. You would probably hate the subject.

You might come to wonder what the point of learning English was. In response perhaps the teachers and education system might decide that, to help make English relevant to students, they need to introduce more "Applied English". This means teaching English students with examples from "real life" (for varying degrees of "real") where English skills are important, like how to read a contract and locate the superfluous comma. Maybe (in an effort by the teachers to be "trendy") you'll get lessons on formal diary composition so you can better update your MySpace page. All of that, of course, will be taught using a formulaic cookbook approach based on templates, with no effort to consider underlying principles or the larger picture. Locating the superfluous comma will be a matter of systematically identifying subjects, objects, and verbs and grouping them into clauses until the extra comma has been caught. Your diary will be constructed from a formal template that leaves a few blanks for you to fill in. Perhaps you might also get a few tasks that are just the same old drills, just with a few mentions of "real world" things to make them "Applied": "Here is an advertisement for carpets. How many adjectives does it contain?".

In such a world it wouldn't be hard to imagine lots of people developing "English anxiety", and most people having a general underlying dislike for the subject. Many people would simply avoid reading books because of the bad associations with English class in school. With so few people taking a real interest in the subject, teachers who were truly passionate about English would become few and far between. The result, naturally, would be teachers who had little real interest in the subject simply following the drilling procedures outlined in the textbooks they were provided; the cycle would repeat again, with students even worse off this time.

And yet this is very much how mathematics tends to be taught in our schools today. There is a great focus on the minutiae of the subject, and almost no effort to help students grasp the bigger picture of why the subject might be interesting, and what it can say about us, and about the world. Mathematics has become hopelessly detail oriented. There is more to mathematics than mindlessly learning formulas and recipes for solving problems. And just like our imaginary example, the response to students lack of interest in mathematics has only served to make the problem worse. The "applications" and examples of using the mathematics in the "real world" are hopelessly contrived at best, and completely artificial at worst, and still keep a laser like focus on formulas and memorizing methods without ever understanding why they work.

Of course the opposite situation, with no focus on details, can be just as bad. Indeed, that is where English instruction finds itself today, with students never learning the spelling, formal grammar, and vocabulary needed to decently express the grand big picture ideas they are encouraged to explore. What is needed is a middle ground. Certainly being fluent in the basic skills of mathematics is necessary, just as having a solid grounding in spelling and grammar is necessary. What is lacking in mathematics instruction is any discussion of what mathematics is, and why mathematics works as well as it does.

The discovery and development of mathematics is one of the great achievements of mankind -- it provides the foundation upon which almost of all modern science and technology rests. This is because mathematics, as the art of abstraction, provides us the with ability to make simple statements that have incredibly broad application. For example, the reason that numbers and arithmetic are so unreasonably effective is that they describe a single simple property that every possible collection possesses, and a set of rules that are unchanged regardless of the specific nature of the collections involved. No matter what collection you consider, abstract or concrete, it has a number that describes its size; no matter what type of objects your collections are made up of, the results of arithmetic operations will always describe the resulting collection accurately. Thus the simple statement that 2 + 3 = 5 is a statement that describes the behaviour of every possible collection of 2 objects, and every possible collection of 3 objects. Algebra can be viewed the same way, except that instead of abstracting over collections we are abstracting over numbers: elementary algebra is the combination of objects that represent any possible number (as numbers represent any possible collection with the given quantity), and the set of arithmetic rules for which all numbers behave identically. Numbers let us speak about all possible collections, and algebra lets us speak about all possible numbers. Each layer of abstraction allows us to use an ever broader brush with which to paint our vision of the world.

If you climb up those layers of abstraction you can use that broad brush to paint beautiful pictures -- the vast scope of the language that mathematics gives you allows simple statements to draw together and connect the unruly diversity of the world. A good mathematical theorem can be like a succinct poem; but only if the reader has the context to see the rich connections that the theorem lays bare. Without the opportunity to step back and see the forest for the trees, to see the broad landscape that the abstract nature of mathematics allows us to address, it is rare for people to see the elegance of mathematical statements. By failing to address how mathematics works, how it speaks broadly about the world, and what it means, we hobble children's ability to appreciate mathematics -- how can they appreciate something when they never learn what it is? The formulas and manipulations children learn, while a necessary part of mathematics, are ultimately just the mechanics of the subject; equally important is why those mechanics are valuable, not just in terms of what they can do, but in terms of why they can do so much.

So why is it that this broader view is so rarely taught? There are, of course, many reasons, and it is not worth trying to discuss them all here. Instead I will point to one reason, for which clear remedies to exist, and immediate action could be taken. That reason is, simply, that far too many people who teach mathematics are unaware of the this broader view themselves. It is unfortunately the case that it is only at the upper levels of education, such as university, that any broader conception about mathematics becomes apparent. Since it is rare for people going into elementary school teaching to take any university level mathematics, the vast majority of elementary teachers -- the math teachers for all our children in their early years -- have little real appreciation of mathematics. They teach the specific trees outlined in textbooks, with no real idea of forest. A simple but effective measure that could be taken is to provide stronger incentives and encouragement for prospective elementary school teachers to take extra math; whether it takes the form of courses, or math clubs, doesn't matter, the aim is to get teachers more involved and better exposed to mathematics in general so that they can become familiar with the richer world beyond the specific formulas and algorithms. This exact approach was tried in Finland as part of their LUMA project starting in 1992. As a result the number of teachers graduating with higher level had increased dramatically by 1999. And the results are also clear: Finland finished first, showing continued improvement in mathematics and science, in the 2003 PISA survey of the reading, math, and science skills of 15-year-olds in OECD countries (Finland finished second, just behind Hong Kong, in the mathematics section). Finland has continued to do extremely well in other more recent (though less major) studies.

Whether you view mathematics as an important subject or not, it is hard to deny that, currently, it is being taught poorly in many countries around the world. With such scope for improvement, and clear examples such as Finland showing the way, isn't it time that we took at least some of the obvious steps toward improving the quality of mathematics education?

Editorial

Journal Journal: Open Source Press Relations

In my copious free time, I pretend to be a journalist. Aside from ranting on Slashdot, I have a couple of weekly-ish columns that I fill with opinions. In the last six months, I have tried to write articles about the BSD family. In preparation for these, I emailed members of the projects with some questions. The differences in the replies were quite surprising:
  • OpenBSD: The team gave me some really good feedback. Not everyone replied, but those who did gave some very interesting material.
  • NetBSD: I'd not used NetBSD much (a bit on some old SPARC32 machines), so I needed a lot of input here. The people I contacted forwarded my questions on to others, collected replies and gave me a huge amount to work with.
  • FreeBSD: This was my major disappointment. I've used FreeBSD for ages, and was looking forward to writing the article. I sent a message to their release engineering mailing list saying I would be interested in writing an article about the next release, and asking for input. It was ignored for a month, then I got one reply suggesting some people to contact. The only one of these to reply did so with a flame. I cancelled the idea of a FreeBSD article as a result, since I wasn't in the right frame of mind to write anything good about the project afterwards.
  • DragonFly BSD The only person I bothered contacting was Matt Dillon, since DragonFly is really his baby. Matt responded promptly with incredibly detailed answers. I'm still in the middle of writing the DragonFly article, but it's a lot of fun to do.

The NetBSD and OpenBSD articles got between 15-30K unique readers in the first seven days. I don't have figures for after that. I've been contacted by a few people who said they started using NetBSD as a result of the article. The moral of this story? If you want free publicity, try being polite.

User Journal

Journal Journal: House of Commons Technology

A little while ago, I emailed my MP about the report published by the BBC saying how great it would be if they made their programming available online using Windows Media DRM (just as the EU is prosecuting Microsoft over exactly that product).

Today, I got a reply, saying:

Thank you for your communication of the
1/2/2007, By E-Mail
which will receive attention

Now, normally, I would expect a reply of this nature to be sent by email, since it's basically an auto-responder. In this case, however, it was sent via a different mechanism. Second class mail.

Yes, my MP employs someone to act as an email auto-responder, replying by postcard to all emails. Isn't technology great?

Technology (Apple)

Journal Journal: Apple Discontinues Mail-in Repairs in the UK 2

Apple have quietly discontinued their mail-in repair service in the UK. While the terms of the AppleCare agreement still state that they offer it, and on-site repair in some cases, they have closed their repair centre and are telling customers to take their machines to the nearest authorised service centre. These are few and far between in the UK; for a lot of people the nearest one is several hours away.

Ping Wales have the full story. From the article:

A straw poll of businesses in Wales which use Macs reveals that no business customers have been informed of the change to the repair service.

Apparently customers were not the only ones kept in the dark over this:

Apple resellers in the region told Ping Wales that they hadn't been informed of the change either, adding that this did explain why the number of repairs coming in had increased significantly over the last few weeks.

User Journal

Journal Journal: Frits Post!

Last week, at a conference, I met someone called Frits Post. He seemed like a really nice guy, but I couldn't help wondering if he regularly posted here...
AMD

Journal Journal: Who Makes Nice Opteron Systems?

I have been told the I am allowed to spend some equipment budget on a nice dual processor system. I am doing work that requires more than 4GB of address space and would benefit from good threading performance. As far as I can see, this means Solaris on Opteron (much as I like SPARC, it doesn't cut it in terms of price / performance for machines under about 8 CPUs these days). Oh, and I need good floating point performance, which rules out Niagara.

Can anyone recommend a good supplier for Opteron machines at a reasonable price? I need a minimum of two CPUs (or cores), a reasonably sized (but not necessarily fast) hard disk, a couple of GB of RAM. It's going to run headless, so no graphics card is required (the Sun workstation line looks nice, but I object to spending money on an nVidia Quadro card that is never going to be used).

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