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Cross-posted from StackOverflow:

I wrote a little toy script to solve this type of game, and put it on my new micro EC2 instance. It works perfectly, but while it takes around 0.5 seconds to run a local version, and takes under 0.5 seconds to run both the local and the version on my home computer, running the version on the EC2 instance takes over 2 minutes.

Python has the cpu pegged at 99% the entire time. Only 7.4% memory usage, consistently, and no swapping. The only guess I have is initialization time for on EC2, but if it were that, why would it be ~200x faster on my own computer with

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Out of curiosity, which pybloomfilter are you using? I'm getting "TypeError: too many initializers" on the scrambled = line. Or is there something else that's causing that error? – Dennis Williamson Dec 20 '10 at 18:44
Instead of pybloom, I went with pybloomfiltermmap from this post. It works fantastically well in every use case except when called by on EC2. – user61633 Dec 20 '10 at 20:11

Amazon micro instances only guarantee a small amount of CPU, but will occasionally burst additional CPU resources. If you have a CPU intensive script, it will run slowly on a micro instance most of the time by design. More information is in the Amazon announcement here:

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