On Wed, Oct 26, 2016 at 12:21 AM, Junio C Hamano <gitster@xxxxxxxxx> wrote: >> Timestamps allow us to say, ok this base index file has not been read >> by anybody for N+ hours (or better, days), it's most likely not >> referenced by any temporary index files (including >> $GIT_DIR/index.lock) anymore because those files, by the definition of >> "temporary", must be gone by now.... > > and if we guessed wrong, users will have a "temporary index" that > they meant to keep for longer term that is now broken here. I am > not sure if that risk is worth taking. Even if we ignore user index files (by forcing them all to be stored in one piece), there is a problem with the special temporary file index.lock, which must use split-index because it will become the new index. Handling race conditions could be tricky with ref counting. Timestamps help in this regard. -- Duy