On Wed, Oct 03 2018, SZEDER Gábor wrote: > On Wed, Oct 03, 2018 at 03:23:57PM +0200, Ævar Arnfjörð Bjarmason wrote: >> Don't have time to patch this now, but thought I'd send a note / RFC >> about this. >> >> Now that we have the commit graph it's nice to be able to set >> e.g. core.commitGraph=true & gc.writeCommitGraph=true in ~/.gitconfig or >> /etc/gitconfig to apply them to all repos. >> >> But when I clone e.g. linux.git stuff like 'tag --contains' will be slow >> until whenever my first "gc" kicks in, which may be quite some time if >> I'm just using it passively. >> >> So we should make "git gc --auto" be run on clone, > > There is no garbage after 'git clone'... "git gc" is really "git gc-or-create-indexes" these days. >> and change the >> need_to_gc() / cmd_gc() behavior so that we detect that the >> gc.writeCommitGraph=true setting is on, but we have no commit graph, and >> then just generate that without doing a full repack. > > Or just teach 'git clone' to run 'git commit-graph write ...' Then when adding something like the commit graph we'd need to patch both git-clone and git-gc, it's much more straightforward to make need_to_gc() more granular. >> As an aside such more granular "gc" would be nice for e.g. pack-refs >> too. It's possible for us to just have one pack, but to have 100k loose >> refs. >> >> It might also be good to have some gc.autoDetachOnClone option and have >> it false by default, so we don't have a race condition where "clone >> linux && git -C linux tag --contains" is slow because the graph hasn't >> been generated yet, and generating the graph initially doesn't take that >> long compared to the time to clone a large repo (and on a small one it >> won't matter either way). >> >> I was going to say "also for midx", but of course after clone we have >> just one pack, so I can't imagine us needing this. But I can see us >> having other such optional side-indexes in the future generated by gc, >> and they'd also benefit from this. >> >> #leftoverbits
