Re: [Monotone-devel] Re: linus talk on git

[Nathaniel Smith]

On Mon, May 21, 2007 at 09:25:24AM -0400, Jack Lloyd wrote:
> I wouldn't think so, RSA verification is pretty cheap.

Also, you mostly don't have to even do it -- it turns out the
interesting operations are things like "heads", where you just need to
know the most recent valid signatures with some property, and in that
case you can optimize away basically all of the trust checking.  (I
think we validate ~10 certs per call to heads, or something like
that.)

> Though as an aside: it appears that the changelog message is its own
> cert (looking at 0.35 cert.cc here). Why is that? I would think it
> more natural to store that in a hash->string value (like file
> contents), and have the revision cert reference the hash. That way you
> avoid a sign/verify, and allows you to coalesce common log messages
> (just wrote a Perl script to go through the Subversion history on a
> repo at work, and found many duplicates like "first revision", "oops",
> "bug fix", "checkpoint", etc). Since you avoid the extra signature it
> should be an overall space win, too...

I note that "first revision", "oops", "bug fix" and "checkpoint" are
all strings with the property that they are shorter than their hash,
which makes coalescing them a bit pointless :-).

-- Nathaniel

-- 
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