Re: git status: small difference between stating whole repository and small subdirectory

On Mon, Feb 20, 2012 at 9:06 PM, Jeff King [off-list ref] wrote:

Interestingly, on my git.git repo, I had an empty cache. Running "git
read-tree HEAD" filled it (according to test-dump-cache-tree). It seems
that running "git checkout" empties the cache.  So perhaps git could do
better about keeping the cache valid over time.

For fast forward case when result index matches 100% destination tree,
yeah we should repopulate cache-tree. "git reset" does that. Not sure
about other cases though. I don't think we can keep track what
subtrees are unchanged after unpack_trees() in order to keep them.
-- 
Duy