Re: Using HTTP pipelining for substitutes

[Ludovic Courtès]

address@hidden (Ludovic Courtès) skribis:

> The new ‘wip-http-pipelining’ branch changes ‘guix substitute-binary’ so
> that, instead of using the current brute force approach—a bunch of
> threads performing HTTP GETs[*] in parallel to hydra.gnu.org–, it sends all
> HTTP GET requests in a row and then reads responses (“HTTP pipeline”.)
>
> I suspect it performs more or less the same as the brute force approach,

Actually that intuition was wrong, because it takes some time for Hydra
to process .narinfo GET requests.

Namely: it runs at 3.5 reqs/s. when signing narinfos (our case), and
37.0 reqs/s. when not signing them.

I’ll see if we can adjust Hydra to do some caching.

Ludo’.