On Tue, Jan 07, 2014 at 05:08:56PM -0500, Jeff King wrote: > > OK. I agree with that line of thinking. Let's take it one step at > > a time, i.e. do c. and also use warn_on_object_refname_ambiguity in > > "rev-list --stdin" first and leave the simplification (i.e. b.) for > > later. > > Here's a series to do that. The first three are just cleanups I noticed > while looking at the problem. > > While I was writing the commit messages, though, I had a thought. Maybe > we could simply do the check faster for the common case that most refs > do not look like object names? Right now we blindly call dwim_ref for > each get_sha1 call, which is the expensive part. If we instead just > loaded all of the refnames from the dwim_ref location (basically heads, > tags and the top-level of "refs/"), we could build an index of all of > the entries matching the 40-hex pattern. In 99% of cases, this would be > zero entries, and the check would collapse to a simple integer > comparison (and even if we did have one, it would be a simple binary > search in memory).
That turned out very nicely, and I think we can drop the extra flag entirely. Brodie's patch still makes sense, for people who do want to turn off ambiguity warnings entirely (and I built on his patch, which matters textually for 4 and 5, but it would be easy to rebase). I'm cc-ing Michael, since it is his ref-traversal code I am butchering in the 3rd patch. The first two are the unrelated cleanups from v1. They are not necessary, but I do not see any reason not to include them. [1/5]: cat-file: refactor error handling of batch_objects [2/5]: cat-file: fix a minor memory leak in batch_objects [3/5]: refs: teach for_each_ref a flag to avoid recursion [4/5]: get_sha1: speed up ambiguous 40-hex test [5/5]: get_sha1: drop object/refname ambiguity flag -Peff -- To unsubscribe from this list: send the line "unsubscribe git" in the body of a message to majord...@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
