Re: [RFC/PATCH 0/8] Add configuration options for split-index

On Mon, Jul 11, 2016 at 7:22 PM, Christian Couder
[off-list ref] wrote:

Future work
~~~~~~~~~~~

One thing that is probably missing is a mechanism to avoid having too
many changes accumulating in the (split) index while in split index
mode. The git-update-index documentation says:

        If split-index mode is already enabled and `--split-index` is
        given again, all changes in $GIT_DIR/index are pushed back to
        the shared index file.

but it is probably better to not expect the user to think about it and
to have a mechanism that pushes back all changes to the shared index
file automatically when some threshold is reached. The threshold could
be for example when $GIT_DIR/index size is larger than 25% of the
shared index size. Opinions, test results or test ideas are welcome on
this.

Oh yes I would like something like this. I stuck to the basics because
as you see you need to define some criteria to re-split again, but
without experimenting on real repos, I could just have gone the wrong
way. Index file size or the percentage of entries in linked/shared
indexes are two good candidates. You can also just re-split on
commands that likely lead to increasing linked index size a lot (maybe
git-reset), or run long enough that some extra processing won't get
noticed. For example git-gc should definitely re-split if this feature
is on, but I can't say if it's often enough.
-- 
Duy