Thanks for testing it out. The unpack_trees bugfix is especially useful.

There's tons of places where we're using ce_uptodate(ce) that could be
optimized by checking CE_FSMONITOR_VALID. One example is in
run_diff_files in diff-lib.c

Should we add a check for CE_FSMONITOR_VALID in all of them? Should we
do that in this patch? Or should we take the time to refactor and
flesh out bugs in unifying it with CE_UPTODATE? It would be nice to
get more opinions. I've taken a look and believe that it will make
things a little more complicated to merge it with CE_UPTODATE,
especially since it's used in a few places for other reasons like
sparse checkouts. On the other hand, I'm a first time contributor, so
my perspective towards a large refactor like might be too
conservative.


On Tue, Oct 29, 2019 at 1:12 PM Kevin Willford
[off-list ref] wrote:

quoted

On Tuesday, October 29, 2019 1:07 PM Utsav Shah [off-list ref]
wrote:

I'm getting the same test failures with or without
GIT_TEST_FSMONITOR=t/t7519/fsmonitor-all and calling refresh_fsmonitor
in tweak_fsmonitor. Could you share your patch? I'm probably messing
something up, and I can try taking a look at fixing test cases as well.

I have the tests passing with the following commit.

https://github.com/kewillford/git/commit/3b1fdf5a4b1cd1d654b1733ce058faa4f087f75f

Things to note:
1. Not sure if fsmonitor was tested with split index so for now I removed that from the
check of entries in fsmonitor bitmap vs the number of cache entries
2. With these changes update-index was triggering the post-index-change hook with the
updated_skipworktree flag set which it wasn't before.
3. Copied the fsmonitor_last_update to the result index so the fsmonitor data will be
carried over to the new index in unpack_trees.  This is to make sure that the next call
to git will have the fsmonitor data to use.  We found that running `git status` after any
command that ran unpack_trees (checkout, reset --hard, etc.) was very slow the first
call but and subsequent calls were fast.

I'm still testing and reviewing these changes to make sure there isn't something I
have missed and that I made the right changes to the tests that were failing.

Kevin