First run (total) ~28.0 min

Second run (total) ~13.0 min

First run (git) ~6.5 min

Second run (git) ~1.5 min

First run (build_results) ~19.0 min

Second run (build_results) 10.5 min

Hence, the core of building the results is most of the time. But there's still some considerable overhead. I did notice that the result build tool is compiled every time for some reason. And it's not supposed to be :-( As for the core result building.. From eyeing it, it seems the slow part is the XML reading. And then there's git.. We could probably reduce that time by only getting selected portions of Boost (enough to build the tools).