From: Linus Torvalds Date: Fri, 10 Aug 2007 19:53:51 +0000 (-0700) Subject: Optimize the three-way merge of git-read-tree X-Git-Tag: v1.5.3-rc5~30 X-Git-Url: https://git.tokkee.org/?a=commitdiff_plain;h=566b5c057c452d04605805ea2f7af210c6fb9b59;p=git.git Optimize the three-way merge of git-read-tree As mentioned, the three-way case *should* be as trivial as the following. It passes all the tests, and I verified that a conflicting merge in the 100,000 file horror-case merged correctly (with the conflict markers) in 0.687 seconds with this, so it works, but I'm lazy and somebody else should double-check it [jc: followed all three-way merge codepaths and verified it removes when it should]. Without this patch, the merge took 8.355 seconds, so this patch really does make a huge difference for merge performance with lots and lots of files, and we're not talking percentages, we're talking orders-of-magnitude differences! Now "unpack_trees()" is just fast enough that we don't need to avoid it (although it's probably still a good idea to eventually convert it to use the traverse_trees() infrastructure some day - just to avoid having extraneous tree traversal functions). Signed-off-by: Linus Torvalds Signed-off-by: Junio C Hamano --- diff --git a/unpack-trees.c b/unpack-trees.c index fda7729f1..ccfeb6e24 100644 --- a/unpack-trees.c +++ b/unpack-trees.c @@ -667,7 +667,6 @@ int threeway_merge(struct cache_entry **stages, int no_anc_exists = 1; int i; - remove_entry(remove); for (i = 1; i < o->head_idx; i++) { if (!stages[i] || stages[i] == o->df_conflict_entry) any_anc_missing = 1; @@ -730,8 +729,10 @@ int threeway_merge(struct cache_entry **stages, } /* #1 */ - if (!head && !remote && any_anc_missing) + if (!head && !remote && any_anc_missing) { + remove_entry(remove); return 0; + } /* Under the new "aggressive" rule, we resolve mostly trivial * cases that we historically had git-merge-one-file resolve. @@ -763,6 +764,7 @@ int threeway_merge(struct cache_entry **stages, if ((head_deleted && remote_deleted) || (head_deleted && remote && remote_match) || (remote_deleted && head && head_match)) { + remove_entry(remove); if (index) return deleted_entry(index, index, o); else if (ce && !head_deleted) @@ -785,6 +787,7 @@ int threeway_merge(struct cache_entry **stages, verify_uptodate(index, o); } + remove_entry(remove); o->nontrivial_merge = 1; /* #2, #3, #4, #6, #7, #9, #10, #11. */