Re: Poor performance of git describe in big repos

Thomas Rast [off-list ref] writes:

I had a brief look around sha1_file.c, in particular sha1_object_info,
and it turns out we lack the "deflate only early part" logic as I
suspected.  So that'll have to be fixed first.  After that I *think* it
should automatically carry over into the tag readers.

Strike that, I'm wrong.  sha1_object_info is fast even for these big
loose objects.

The culprit, according to some callgrind investigation, is
lookup_commit_reference_gently() [for the unannotated case] or
deref_tag() [annotated case] calling parse_object().

-- 
Thomas Rast
trast@{inf,student}.ethz.ch