Junio C Hamano <junkio@xxxxxxx> writes: > It may be interesting to run tests on real merges (I believe the > kernel repository has a handful merges that have more than one > merge bases) to see how effective the current clean-up pass is. > It may turn out to be ineffective in practice, in which case we > could kill it off. So I counted. There are 23 commits in the kernel history that have more than one merge-bases. The current merge-base code tells us that all of them have two merge-bases. None of them suffers from the horizon effect; the two bases are not ancestor/descendant of each other. A good news is that get_merge_bases() gives the same answer without the clean-up pass mark_reachable_commits(). d0e5f39f1ee2e55d140064bb6d74c8bad25d71d0 361ea93cbff0e42cbc6a0f3c7a8238db9ed15648 4b2d9cf00962d0a0e697f887f3ecaa155cbde555 ba9b28d19a3251bb1dfe6a6f8cc89b96fb85f683 db21e578e551421d76641d72cb3f8296ed3f9e61 b425c8c5922562c562dc55a636c3c8d758ed6d17 2e9ff56efbc005ab2b92b68df65940c7459446c6 75e47b36004d136edff68295420424cba3a5ccd0 c45ae87ec9d03c9adfc466a6b560cb38b154813a 09e4f9029da1b53e835555c353a89c36b71233b0 0b310f36d7d96e27f6941ec0f9b95e15142f1e78 db9ace7083dbdcc3d02bdd6a1d26132c80b5b726 80c7af4074cbb4cb6be5d35c443ea6d5e8838a84 701db69d6647f61e4660c9102d7f2fd5dffc203d 5e3c2b95dd560baa41b08c8f5f00bbd6fbeebdcb c7fb577e2a6cb04732541f2dc402bd46747f7558 ba9b543d5bec0a7605952e2ba501fb8b0f3b6407 84ffa747520edd4556b136bdfc9df9eb1673ce12 da28c12089dfcfb8695b6b555cdb8e03dda2b690 3190186362466658f01b2e354e639378ce07e1a9 0c168775709faa74c1b87f1e61046e0c51ade7f3 0e396ee43e445cb7c215a98da4e76d0ce354d9d7 467ca22d3371f132ee225a5591a1ed0cd518cb3d - : 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