Week 2 Tutorial: One headless run

Get the specimen running on your own machine with no window open, and time it.

4 March 2027

Before the tutorial#

Clone the specimen and install its dependencies. Bring a laptop that can run Node.

In the tutorial#

Call the headless runner once with seed 97 and an ordinary simulated player. Write down three things: how long it took, whether the run was won or lost, and the second it ended on. For reference, a 2024 laptop takes about 10 ms on the first call and under 4 ms once warm, and the run is lost at 69.333 s.

Then run the same seed again. If the two results differ in any digit, something in your setup is reading a clock or a random number it was not handed, and finding it is the rest of your tutorial.

Where it goes wrong#

• Timing the first call. The same run, called eight times in a row, took 10.3 ms, 7.0 ms, 5.3 ms, 4.8 ms and then settled near 3.7 ms. The engine is still compiling the rules the first few times. Time the fifth call, not the first, and say which one you timed.
• Timing the process. Starting Node costs far more than the run does. Put the clock around the run, inside the script.
• Forgetting to hand in the dice. Leave the random source out and the rules fall back to the machine’s own. The same player then ended at 79.5 s and at 59.3 s on two calls, and nothing warned about it.

What a finished answer looks like#

Seed 97, 150 ms player: lost at 69.333 s. Fifth call took 3.7 ms. Run twice, identical to the millisecond.

Afterwards#

The timing is your number for this week’s quiz. Multiply it out: how many runs could you do in the 120 s it takes a person to play one?