From: Junio C Hamano Date: Fri, 21 Feb 2014 17:47:36 GMT Subject: Re: git gc --aggressive led to about 40 times slower "git log --raw" Message-ID: In-Reply-To: Duy Nguyen writes: > For old projects, commits older than 1-2 years is probably less often > accessed and could use some aggressive packing. I used to repack older part of history manually with a deeper depth, mark the result with the .keep bit, and then repack the whole thing again to have the remainder in a shallower depth. Something like: git rev-list --objects v1.5.3 | git pack-objects --depth=128 --delta-base-offset pack would give me the first pack (in real life, I would use a larger window size like 4096), and then after placing the resulting .pack and .idx files along with a .keep file in .git/objects/pack/, running "git repack -a -d" to pack the rest. > This still hits git-blame badly. We could even make sure all > objects "on the blame surface" have short delta chain. But that > may be pushing pack-objects too much. Yes, you can do a similar trick by blaming all the paths that ever existed in the project, parse its --porcelain output to learn all the commits and paths involved, to find the objects that need quicker access. Pack such objects in a pack with a shallow depth, tentatively mark that pack with .keep, repack the remainder with a deep depth, remove .keep from the first pack and mark the new pack with .keep to prevent it from getting repacked, or something like that.