Re: Debugging git-commit slowness on a large repo

Carlos Martín Nieto [off-list ref] writes:

... At one
point, commit forgot how to write the tree cache to the index (a
performance optimisation). Do the times improve if you run 'git
read-tree HEAD' between one commit and another? Note that this will
reset the index to the last commit, though for the tests I image you
use some variation of 'git commit -a'.

Thomas Rast wrote a patch to re-teach commit to store the tree cache,
but there were some issues and never got applied.

Ahh, I forgot all about that exchange.

  http://thread.gmane.org/gmane.comp.version-control.git/178480/focus=178515

The cache-tree mechanism has traditionally been one of the more important
optimizations and it would be very nice if we can resurrect the behaviour
for "git commit" too.