The best way I can understand the popularity of software patents is that they protect incumbent companies from newcomers. Large incumbent companies accumulate patents, they use them to litigate against small newcomers who have no patents of their own, and they form patent-sharing agreements with each other to prevent the same thing from happening to them. Occasionally it comes back to bite one of the incumbents, but for the most part they seem to believe it comes out in their favor.
One place this arrangement fails, though, is if one of the incumbents decides not to play for the long term. See, the reason incumbents don't sue each other over patents is that they fear the counter-suit. It's classic M.A.D.: mutual assured destruction.
However, what if an incumbent is on their way out of the computer business, either because they are shifting focus or because they are retiring? Well, in that case, the fear of a counter-suit would be nonexistent, wouldn't it? Count me in as one who thinks Paul Allen's recent actions suggest he is planning to retire, or at the very least get out of computers. My next best guesses are that he is trying to make some sort of point, or that he is simply unsavvy about the software industry. Neither of these sounds especially likely.
Monday, August 30, 2010
Wednesday, August 11, 2010
Rubik's Cube's difficulty cracked
I'm late to notice this, but recently a team proved that a Rubik's Cube can always be solved in 20 moves or less, regardless of its initial configuration. It had already been proven, back in 1995, that at least one initial configuration requires 20 moves to solve. Thus, all positions can be solved in 20 moves, and some positions require the full 20.
What is particularly interesting is that the these researchers found the 20-move bound by having a computer solve all of the 4E19 initial positions exhaustively. The best proof that didn't do an exhaustive search only proved an upper bound of 22 moves.
I wonder if a human-digestible proof will be found for the 20-move upper bound, or if we'll be left with computers generating the stronger proof? At any rate, this is yet one more problem where a mathematical result depends crucially on some very heavy computation.
What is particularly interesting is that the these researchers found the 20-move bound by having a computer solve all of the 4E19 initial positions exhaustively. The best proof that didn't do an exhaustive search only proved an upper bound of 22 moves.
I wonder if a human-digestible proof will be found for the 20-move upper bound, or if we'll be left with computers generating the stronger proof? At any rate, this is yet one more problem where a mathematical result depends crucially on some very heavy computation.
Thursday, July 8, 2010
Pseudonimity
People participating in online forums are better off being identified by pseudonyms rather than by their legal names. This is pretty engrained in me after many years of participating in such forums, so it takes some soul searching to explain. Let me try and distill out three points.
First, people have multiple parts of their lives, and they don't want them to mix. There are many reasons why this is good, but at the very least let's observe that this is how most people arrange their lives. There's work, and there's play. On the Internet, pseudonyms allow these separate lives to be separated more effectively.
Second, it fights prejudice. What makes prejudice so bad is not just that people are judged wrongly, but that they are judged wrongly using information that really should be irrelevant. Using pseudonyms means that this irrelevant information can be completely non-present. If your name is Julie or Juan or Duk-Kwan, you can expect to get a different--unfairly different--reaction if people learn your name, and thus your probable gender or ethnicity.
Finally, let me emphasize that pseudonyms are not anonymous. They are actual names, and they accumulate a reputation just like any other name. "Tom Cruise" is a pseudonym, but it's a name that has a very strong reputation (of one sort or another). So it goes with online pseudonyms, as well.
Given this, readers won't be surprised that I oppose Blizzard's trend toward using a "real" ID, "real" meaning a name on the credit card that pays for an account. Already, if you want to participate in cross-server chat on their games, you have to expose your credit-card name to everyone on your cross-server friends list. Now they are talking about changing the official forums to use credit-card names rather than
The idea seams to be that if people post under their credit-card names rather than their Warcraft character names, then they'll post better content to the forums. I don't agree this is a sufficient reason for the change, and I don't even think they are going to get the result the hope for.
Aside from all this heavy stuff, why in the world is a fantasy online computer game going this way? Grey Shade says it best:
UPDATE: Blizzard cancelled enforced real names on the forums, and said they are going to strive to prevent real names leaking in-game for people who want that. Good choices! Crisis averted. Everyone can go back, now, to killing Internet dragons.
First, people have multiple parts of their lives, and they don't want them to mix. There are many reasons why this is good, but at the very least let's observe that this is how most people arrange their lives. There's work, and there's play. On the Internet, pseudonyms allow these separate lives to be separated more effectively.
Second, it fights prejudice. What makes prejudice so bad is not just that people are judged wrongly, but that they are judged wrongly using information that really should be irrelevant. Using pseudonyms means that this irrelevant information can be completely non-present. If your name is Julie or Juan or Duk-Kwan, you can expect to get a different--unfairly different--reaction if people learn your name, and thus your probable gender or ethnicity.
Finally, let me emphasize that pseudonyms are not anonymous. They are actual names, and they accumulate a reputation just like any other name. "Tom Cruise" is a pseudonym, but it's a name that has a very strong reputation (of one sort or another). So it goes with online pseudonyms, as well.
Given this, readers won't be surprised that I oppose Blizzard's trend toward using a "real" ID, "real" meaning a name on the credit card that pays for an account. Already, if you want to participate in cross-server chat on their games, you have to expose your credit-card name to everyone on your cross-server friends list. Now they are talking about changing the official forums to use credit-card names rather than
The idea seams to be that if people post under their credit-card names rather than their Warcraft character names, then they'll post better content to the forums. I don't agree this is a sufficient reason for the change, and I don't even think they are going to get the result the hope for.
Aside from all this heavy stuff, why in the world is a fantasy online computer game going this way? Grey Shade says it best:
But that’s it, you get it? That’s why I play. That’s why my friends play. Because we like to come home from a long day of being John Smith or Jane Doe and get on the computer and MURDER SOME REALLY AWESOME INTERNET DRAGONS.
UPDATE: Blizzard cancelled enforced real names on the forums, and said they are going to strive to prevent real names leaking in-game for people who want that. Good choices! Crisis averted. Everyone can go back, now, to killing Internet dragons.
Thursday, July 1, 2010
A foreign film I'd love to see
Java 4 ever is a hilarious trailer for a made up movie. It has all the cliches from a Hollywood warm-human-tale kinda movie, but instead of being about forbidden cross-sect love, it's about open computer standards.
Beware that the trailer is R rated at one point.
HT Ted Neward
Beware that the trailer is R rated at one point.
HT Ted Neward
Tuesday, June 29, 2010
Wrapping code is slow on Firefox
UPDATE: Filed as bug 576630 with Mozilla. It would be great if this slowdown can be removed, because wrapping chunks of code in a function wrapper is a widely useful tool to have available.
I just learned, to my dismay, that adding a single layer of wrapping around a body of JavaScript code can cause Firefox to really slow down. That is, there are cases where the following code takes a second to load:
Yet, the following equivalent code takes 30+ seconds to load:
This is disappointing, because wrapping code inside a function is a straightforward way to control name visibility. If this code defines a bunch of new functions and vars, you might not want them all to be globally visible throughout a browser window. Yet, because of this parsing problem on Firefox, simply adding a wrapper function might not be a good idea.
After some investigation, the problem only arises when there are a lot of functions defined directly inside a single other function. Adding another layer of wrapping gets rid of the parse time problem. That is, the following parses very quickly:
Of course, to use this approach, you have to make sure that the cross-references between the statements still work. In general this requires modifying the statements to install and read properties on some object that is shared among all the chunks.
I wrote a Scala script named genslow.scala that generates two files: test.html and module.html. Load the first page in firefox, and it will cause a load of the second file into an iframe. An alert will pop up once all the code is loaded saying how long the load took.
There are three variables the top of the script that can be used to modify module.html. On my machine, I get the following timings:
default: 1,015 ms
jslink: 1,135 ms
wrapper: 34,288 ms
wrapper+jslink: 52,078 ms
wrapper+jslink+chunk: 1,188 ms
The timings were on Firefox 3.6.3 on Linux. I only report the first trial in the above table, but the pattern is robust across hitting reload.
I just learned, to my dismay, that adding a single layer of wrapping around a body of JavaScript code can cause Firefox to really slow down. That is, there are cases where the following code takes a second to load:
statement1
statement2
...
statement1000
Yet, the following equivalent code takes 30+ seconds to load:
(function() {
statement1
statement2
...
statement1000
})()
This is disappointing, because wrapping code inside a function is a straightforward way to control name visibility. If this code defines a bunch of new functions and vars, you might not want them all to be globally visible throughout a browser window. Yet, because of this parsing problem on Firefox, simply adding a wrapper function might not be a good idea.
After some investigation, the problem only arises when there are a lot of functions defined directly inside a single other function. Adding another layer of wrapping gets rid of the parse time problem. That is, the following parses very quickly:
(function() {
(function() {
statement1
..
statement10
})()
...
(function() {
statement991
...
statement1000
})()
})()
Of course, to use this approach, you have to make sure that the cross-references between the statements still work. In general this requires modifying the statements to install and read properties on some object that is shared among all the chunks.
Example Code and Timings
I wrote a Scala script named genslow.scala that generates two files: test.html and module.html. Load the first page in firefox, and it will cause a load of the second file into an iframe. An alert will pop up once all the code is loaded saying how long the load took.
There are three variables the top of the script that can be used to modify module.html. On my machine, I get the following timings:
default: 1,015 ms
jslink: 1,135 ms
wrapper: 34,288 ms
wrapper+jslink: 52,078 ms
wrapper+jslink+chunk: 1,188 ms
The timings were on Firefox 3.6.3 on Linux. I only report the first trial in the above table, but the pattern is robust across hitting reload.
Wednesday, June 23, 2010
Mass Effect for Xb^H^H Windows
I just got Mass Effect for Windows, but after reading the README file, I fear for the computer it will be installed on:
Okay, I can see that being hard to fix. Load/save systems are often tricky, and being between zones would only make it worse. It goes on, though:
Um, wow. That's it? It just doesn't work if you have this card?
Or that one?
That one, either? Methinks they should list the cards it does work with, and on the box, not in a README file.
Err, okay. This kinda goes along with "minimum system requirements".
"Required". As if they couldn't have precomputed shaders for the 10-20 most common resolutions. As if any other game has this problem.
After reading this, I wasn't confident. Sure enough, I get a General Protection Fault on startup. As extra weirdness, it reports a "file not found" exception from within some graphics library.
Overall, I guess what the developers did is make the Xbox version first, and then make a half-hearted attempt to port to Windows. If I'd realized how flaky this is, I probably would have passed it over.
Game Known Issues
-----------------
In Mass Effect you will occsaionally find elevators that connect different
locations. While riding in an elevator the game is loading significant amounts
of information and modifying data. We recommend against saving the game after
an elevator is activated until the player departs the elevator. Saving during
elevator trips can occasional cause unusual behaviors.
Okay, I can see that being hard to fix. Load/save systems are often tricky, and being between zones would only make it worse. It goes on, though:
Mass Effect does not run on a system using a GMA X3000 video card, a general
protection fault error appear after double clicking the start icon.
Um, wow. That's it? It just doesn't work if you have this card?
Mass Effect does not run optimally on the Sapphire Radeon x1550 series of video
cards. We recommend that Mass Effect is not played on a system with this video
card.
Or that one?
Mass Effect does not run optimally on the NVIDIA GeForce 7100 series of video
cards. We recommend that Mass Effect is not played on a system with this video
card.
That one, either? Methinks they should list the cards it does work with, and on the box, not in a README file.
Mass Effect does not run optimally on a computer with a Pentium 4 CPU with a
FSB below 800 MHz under Windows Vista. We recommend that Mass Effect is not
played on a system with this CPU and operating system combination.
Err, okay. This kinda goes along with "minimum system requirements".
The the NVIDIA 8800 Series of video cards can require significant time (30
seconds or more) to change resolutions. This is due to a required
recalculation of thousands of video shaders.
"Required". As if they couldn't have precomputed shaders for the 10-20 most common resolutions. As if any other game has this problem.
After reading this, I wasn't confident. Sure enough, I get a General Protection Fault on startup. As extra weirdness, it reports a "file not found" exception from within some graphics library.
Overall, I guess what the developers did is make the Xbox version first, and then make a half-hearted attempt to port to Windows. If I'd realized how flaky this is, I probably would have passed it over.
Friday, June 18, 2010
Commutative? Associative? Idemflabitical?!
Guy Steele has a noble goal in mind for the Fortress library:
It's a good goal. Using technical terms often obscures the real point one is trying to make. Worse, technical terms are often dress up a claim to sound like it says much more than it does. For all kinds of reasons, it is better to well-known informal terms whenever they will work.
Nonetheless, I am not so sure about changing terms like commutative and associative in the Fortress library. It looks like a case where the hard part is not in the terminology, but in the underlying theory itself. Once a programmer understands the theory well enough to work with the library, they'll almost certainly know the standard formal terms anyway.
A similar issue come up for Scala, where writers of very flexible libraries end up working with rather complicated static types. In such cases, there is no getting around understanding how the Scala type system works. The Scala collections library is deep mojo.
That doesn't mean the complexity must leak out to users of the library, however. In both cases, the designers of core libraries must think hard, because they are working with deep abstractions. If the designers do well, then users of these libraries will find everything working effortlessly.
I have noticed that when I give talks about Fortress and start talking about the importance of algebraic properties for parallel programming, I often see many pairs of eyes glaze over, if only a bit. It occurs to me that maybe not everyone is conversant or comfortable with the terminology of modern albegra (maybe they had a bad experience with the New Math back in the 1960s, a fate I barely escaped), and this may obscure the essential underlying ideas, which after all are not that difficult, and perhaps even obvious to the average programmer when explained in everyday terms.
It's a good goal. Using technical terms often obscures the real point one is trying to make. Worse, technical terms are often dress up a claim to sound like it says much more than it does. For all kinds of reasons, it is better to well-known informal terms whenever they will work.
Nonetheless, I am not so sure about changing terms like commutative and associative in the Fortress library. It looks like a case where the hard part is not in the terminology, but in the underlying theory itself. Once a programmer understands the theory well enough to work with the library, they'll almost certainly know the standard formal terms anyway.
A similar issue come up for Scala, where writers of very flexible libraries end up working with rather complicated static types. In such cases, there is no getting around understanding how the Scala type system works. The Scala collections library is deep mojo.
That doesn't mean the complexity must leak out to users of the library, however. In both cases, the designers of core libraries must think hard, because they are working with deep abstractions. If the designers do well, then users of these libraries will find everything working effortlessly.
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