Investigating Performance Changes with git bisect

This week, I have been working an issue with LALRPOP. Basically, at some point there was a performance degradation on a newer version of the library. Niko Matsakis mentioned that this is likely due to failing to cache some regular expressions that we need repeatedly. I assume he’s correct, but I want to understand how this performance degradation was introduced, and I’m very new to this code base, so I’m going to try to find the change that introduced it. To find this change, I will use a tool called git bisect. Continue reading “Investigating Performance Changes with git bisect”