Re: [RFC] Bump {diff,merge}.renameLimit ?

On Sat, Jul 10 2021, Elijah Newren wrote:

I'm considering bumping {diff,merge}.renameLimit, which control the
quadratic portion of rename/copy detection.  Should they be bumped?
If so, moderately higher, or much higher?

I lean towards a moderate bump for diff.renameLimit, and preferably
more than just a moderate bump for merge.renameLimit.  I have
calculations for what "moderate" translates to, based on a number of
assumptions.  But there's several reasons to break with past
guideposts for how these limits were picked.  See below for various
arguments in each of the directions.

So...thoughts?

I think the most relevant is something you didn't state: That when this
limit was introduced (well, diff.*, not merge.*) there was no progress
output in git.

We should err entirely on producing consistent and predictable results,
and not change how git works when we it hits some arbitrary limit. To
the extent that this is needed it's sufficient to opt-in to it, i.e. we
do/should show a progress bar, advice() etc. showing why we're doing
this much work, so those users can adjust the limit (or not).