[PATCH 2 of 2] changegroup: skip delta when the underlying revlog do not use them

[Pierre-Yves David]

On 10/14/2016 09:01 AM, Gregory Szorc wrote:
> Cool. I was going to author this patch when I got back home!
>
> This patch will result in CPU regression for old clients having to re-deltify. It would be nice to have numbers for that. I'm optimistic it is roughly the same as the server gains and it won't be significant enough to not take the patch. We also don't have a perf* command to measure changegroup application for a single component IIRC. So getting data isn't trivial :/

As you just said, the redeltifying are probably around the same cost 
than the one we save with this patch (6 seconds for a full Mozilla 
clone). The extra cost seems reasonable to me in that case.

Cheers,

-- 
Pierre-Yves David