Re: [PATCH v2 0/2] do_compare_entry: use already-computed path

David Turner [off-list ref] writes:

On Mon, 2015-12-21 at 15:34 -0800, Junio C Hamano wrote:

quoted

Great. Thanks, will queue w/o 1/2 (though I do not think it would
hurt).

On Mon, Dec 21, 2015 at 3:33 PM, David Turner <
dturner@twopensource.com> wrote:

quoted

On Mon, 2015-12-21 at 15:27 -0800, Junio C Hamano wrote:

quoted

Thanks.  Does the number still stay at 25% improvement?

Yes.

BTW, that function, via ce_in_traverse_path, gets called about 40
million times when switching (checking out) between master and a
branch that's a few months old (and that contains relatively small
changes from master-as-of-then. Our repo only has approximately a
quarter -million files.  This seems somewhat unreasonable to me,
but I haven't really looked into what's going on.  Do you happen
to know why this is and whether it is likely to be a bug?

That does sound excessive; smells like somebody is being overly
cautious (i.e. a performance bug).

We might be seeing something similar to what e53e6b44 observed and
attempted to correct.  I dunno.