Re: [Monotone-devel] speed of "mtn ls branches"

[Nathaniel Smith]

On Thu, Jan 17, 2008 at 10:58:14AM +0100, Thomas Moschny wrote:
> As far as I remember, that's not quite correct. You'd need to validate at 
> least one cert per branch (and even more, if some certs happen to be 
> invalid). That currently makes about 200 checks for the monotone.ca database. 
> And cert validation is expensive. That's exactly why we came up with the idea 
> of interleaving ancestor elimination and cert validation (erase ancestors and 
>  
> failures) for the heads code a while ago, which significantly sped up things.

Cert validation is not super-cheap, no, but validating one cert is
certainly cheaper than loading the revision graph, doing complex graph
operations on it, and validating several dozen certs -- which is what
it costs to perform one "heads" calculation.

-- Nathaniel

-- 
Electrons find their paths in subtle ways.