On Wed, 22 Jul 2009, Linus Torvalds wrote: > > But I'll see if I can dig up my non-binary-search patch and see if I can > make it go faster. My machine is fast, but not so fast that I can't > measure it ;) Oh. We actually merged a fixed version of it. I'd completely forgotten. Enabled with 'GIT_USE_LOOKUP'. But it seems to give worse performance, despite giving me fewer searches: I get 2121 probes with binary searching, but only 1325 with the newton-raphson method (for the non-fixed 'git branch' case). Using GIT_USE_LOOKUP actually results in fewer pagefaults (1391 vs 1473), but it's still slower. Interesting. Carlos, try it on your machine (just do export GIT_USE_LOOKUP=1 time git branch to try it, and 'unset GIT_USE_LOOKUP' to disable it. (And note that the "=1" part isn't important - the only thing that matters is whether the environment variable is set or not - setting it to '0' will _not_ disable it, you need to 'unset' it). With my fix to 'git branch', it doesn't matter. I get the same performance, and same number of page faults (676) regardless. So my patch makes the GIT_USE_LOOKUP=1 thing irrelevant. Linus -- To unsubscribe from this list: send the line "unsubscribe git" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html