Re: [RFC PATCH] git log: support "auto" decorations

Jeff King [off-list ref] writes:

On Thu, May 29, 2014 at 09:54:10PM -0700, Linus Torvalds wrote:

quoted

That said, part of it is just that show-signature is so suboptimal
performance-wise, re-parsing the commit buffer for each commit when
"show_signature" is set. That's just crazy, we've already parsed the
commit text, we already *could* know if it has a signature or not, and
skip it if it doesn't. That would require one of the flag bits in the
object, though, or something, so it's probably not worth doing.

Wow, it's really quite bad. Not only do we spend time on commits that we
could otherwise know do not have signatures, but we actually pull the
buffer from disk, even though we generally have it saved as
commit->buffer.

The one for the signature on the commit itself is me being lazy and
defensive; I did not want to have to worry about people mucking with
what is in commit->buffer for whatever reason (e.g. re-encode in
different charset, etc.) and then asking the signature validated.

The other one for the merge-tag is me just being lazy, as it is
unlikely to be corrupt by any reasonable kinds of mucking with
commit->buffer on a merge.