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Kevin goes to Coachella

I went to the Coachella music festival last week. It was a wild weekend and I will surely go again in the future.

  • I was surprised at how little thought bands put into their onstage appearance and mannerisms. It’s natural for artists to want to focus on their music, and expect others to judge them based on their music, but the fact is the show is more than just the music, especially at a festival where you are going to have more casual fans than a regular concert. The three artists who did the best job of putting on a show were Empire of the Sun, Kanye and Sleigh Bells.
  • Kanye’s show had the clear marks of an egotistical maniac: forty dancers dressed in white, several interludes where he proclaimed his own greatness, and a fifty-foot-tall Greek tragic relief behind him. He let the music play and the dancers dance for about three minutes before appearing. He performed the first song while circling thirty feet above the crowd on a riser. I thought this was brilliant cause it let people take camera phone pictures of Kanye alone against a dark background.
  • Phones were really unreliable for most of the event, so we had to make really concrete plans like “meet at this spot at exactly 6pm” and so on. I don’t understand how people did things before cellphones. People must have just lost each other a lot.
  • At times it seemed like the only thing everyone was doing was just walking around. For a while I flipped out that everyone walking the other way had better information. That theory did not hold weight.
  • As my college career is coming to a close I’m getting really nervous about whether I’ll continue meeting people and making friends. So I’m making more of an effort to talk to strangers. This generally went well. However it’s not a good sign that at a place like Coachella, with 150,000 attractive people in my own demographic, with something really obvious to talk about (the music), and virtually no downside to having a conversation go badly, I only maybe talked to 5 strangers each day.
  • Cell phones aside I was amazed at how smoothly everything ran. I was particularly impressed by these trash cans:

    They are a great example of form following function. The round hole was for round recyclables (bottles, cans). The square hole was for compost items (plates, forks, paper). The other hole was for trash. The one critique I’d have is that the holes were not very large so a drunk or lazy person might just throw their recyclable in the trash. This error may be better than throwing trash in the recycling, however.

  • My favorite acts were Sleigh Bells, Kanye, the Strokes, Cut Copy, Two Door Cinema Club, and Wiz Khalifa. If you have a choice between two acts, choose the louder, more upbeat, or more electronic sounding one.

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links for 2011-04-27

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Presentation on JIT compilers (and the unfortunate sex life of the banana)

Posting's been kind of light, so I'll link to two presentations I've done for class recently. I'm currently taking a course on compilers, which is the best course I've taken in college. Very quickly, your computer can only understand a very limited set of instructions: add 01110011 to 11001011, load eight zeroes and ones from memory (the cache, or random-access memory (RAM)), overwrite a set of zeroes and ones, etc. However, if you had to write entire programs using only this instruction set, it would be hard for programmers to keep track of variable state, to write error-free code and to find bugs when they are made (Notable exception: Roller Coaster Tycoon was written entirely in x86 assembly language, which explains (a) why there has never been a Mac version released, and (b) why RCT3 was so much worse - it was written in a higher-level language by a different company). So what programmers did was invent abstractions - control flow tools like if-then-else branching, while and for loops, as well as data structures like arrays and dictionaries. These allow programmers to write in a more natural language, but programs must be translated - "compiled" - down to machine language. Because this is done automatically, and many people use the same compiler (so everyone benefits from errors caught by one person), generated machine code is usually free of errors. I gave a talk in class on a special type of compiler, called just-in-time (JIT). Normally you write your program, compile it, and then run the machine language. But a JIT compiler is writing and compiling new machine language as the program is running. Here are the slides: There are a few reasons this can be quicker than compiling beforehand ("static" compilation). First, you have more information about the values of variables at runtime that you can use to eliminate redundancy in your code. Second, in the case of loops, where you are following the same code paths hundreds or thousands of times in a row, you can see which paths are being used the most often, and rewrite your code so that the most common code path is executed in a straight line. This is important because modern processors will try to pre-fetch and execute several instructions at a time, and if you keep jumping from place to place in your code, the processor can't execute instructions in advance. I also wrote a paper (and gave a talk) on some of the threats facing the Cavendish banana, which will probably go extinct soon. I've been fortunate to write papers this year on some fun topics; last semester I was able to cite Robin Hanson, Tyler Cowen, Eliezer Yudkowsky and Alan Turing in one philosophy paper, which was pretty fun. That paper's here. The Unfortunate Sex Life of the Banana

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links for 2011-04-21

  • start using css3 instead of sprites, it's faster (and you don't need photoshop/gimp)
  • He believed that teacher training and other cultural factors have more value. “A good teacher sitting under a tree can do more than a bad teacher in a new building,” he said. “That’s why I don’t want to do school construction anymore. It might have been a mistake. It’s a good instinct, as you want to help, but maybe it’s not the best thing.” I asked about his impressions of Mortenson. “I kind of felt sorry for him,” Rajeev said. “That was my reaction reading the book. He must have low self-esteem.”

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