Three Monkeys, Three Typewriters, Two Days

February 20, 2004

Darin's string changes

Darin has more or less finished landing his string changes on the trunk. The upshot is:

  1. Pageload time went down by about 2-3%.
  2. Startup time went down by about 7-8%.
  3. Window open time went down by about 3-4%.
  4. Codesize went down by several hundred kilobytes (ranging from about 150kB to 500kB or so depending on the exact OS/compiler/flags one looks at). That's around 2% of total codesize. A bit over half the savings was codesize reduction in core code.

Darin, dbaron, jst, dougt, and all others who helped make this patch happen deserve a big thank you.

Posted by bzbarsky at 1:26 AM

February 3, 2004

Locks and the appearance of security

The gym here has these "heavy-duty theft-resistant" locks they let you use to lock lockers (amazing concept, huh?). I was playing with one of them today. It's a basic combination lock—single dial that goes from 0 to 39, 3-number combination (X, Y, Z), and the following steps to open:

  1. Start at 0.
  2. Turn to the right one full circle and then to X.
  3. Turn to the left one full circle and then to Y.
  4. Turn to the right to Z.
  5. Turn to the left to 0.

When step 5 is done the lock opens.

The first problem is that if you replace step 4 with

  1. Turn to the right to any place past Z and before Y.

the lock still opens when step 5 is done. In my case Z and Y were "34" and "0" respectively, so it's not like they were close together....

The second problem is that the lock makes a nice loud click when Z is reached in step 4 (which admittedly makes the first problem rather academic).

I have to admit that these look more difficult to saw through than typical high-school locker locks, but from a pure codebreaking standpoint they are much easier to open (only about 400 possible combinations, since there is no need to guess Z; on a lock on which all three numbers need to be guessed there are more like 8000 combinations).

Posted by bzbarsky at 10:49 PM

February 1, 2004

Spelling, the Web, the real world, and misspelling terminology.

More and more of my students seem to think that sets can be "seperated". The Web strikes again. Bring on the claims that spelling is arbitrary anyway, that languages evolve, and that misspelling a word is OK if everyone does it. Then consider that this is not a word but a technical term in this case, and misspelling it means that you're no longer talking about the same thing. Goodbye, clarity of expression. Hello, "I'll spell it however I like; the reader can sort it out!"

Posted by bzbarsky at 3:44 PM