On Wed, Oct 03, 2018 at 04:22:12PM +0200, Ævar Arnfjörð Bjarmason wrote:

On Wed, Oct 03 2018, SZEDER Gábor wrote:

quoted

On Wed, Oct 03, 2018 at 04:01:40PM +0200, Ævar Arnfjörð Bjarmason wrote:

quoted

On Wed, Oct 03 2018, SZEDER Gábor wrote:

quoted

On Wed, Oct 03, 2018 at 03:23:57PM +0200, Ævar Arnfjörð Bjarmason wrote:

quoted

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.

Because it happens to be convenient to create those indexes at
gc-time.  But that should not be an excuse to run gc when by
definition no gc is needed.

Ah, I thought you just had an objection to the "gc" name being used for
non-gc stuff,

But you thought right, I do have an objection against that.  'git gc'
should, well, collect garbage.  Any non-gc stuff is already violating
separation of concerns.

 but if you mean we shouldn't do a giant repack right after
clone I agree.

And, I also mean that since 'git clone' knows that there can't
possibly be any garbage in the first place, then it shouldn't call 'gc
--auto' at all.  However, since it also knows that there is a lot of
new stuff, then it should create a commit-graph if enabled.

I meant that "gc --auto" would learn to do a subset of
its work, instead of the current "I have work to do, let's do all of
pack-refs/repack/commit-graph etc.".

So we wouldn't be spending 5 minutes repacking linux.git right after
cloning it, just ~10s generating the commit graph, and the same would
happen if you rm'd .git/objects/info/commit-graph and ran "git commit",
which would kick of "gc --auto" in the background and do the same thing.