Real-world optimization
Last week at work, I was asked to look at one of our verification modules that was taking about three times longer to run than it had in an earlier version. This module takes a set of result files, compares them against another file showing expected results, and reports any discrepancies that are outside the defined margin of error. It’s some pretty heavy work involving hundreds of thousands of data points, and the old version already took more than ten minutes. Increasing the running time by a factor of three just wasn’t acceptable. So I started to look at what was going on.