Re: slowest tap tests - split or accelerate?

Hi,

On 2022-01-18 12:49:16 -0500, Robert Haas wrote:
> Here's a patch that splits up that file.

Ah, nice! The split seems sensible to me.

> Sadly, we've gained about 2.5 seconds of runtime as the price of
> splitting the test. Arguably the options part could be split up a lot
> more finely than this, but that would drive up the runtime even more,
> basically because we'd need more initdbs. So I don't know whether it's
> better to leave things as they are, split them this much, or split
> them more. I think this amount of splitting might be justified simply
> in the interests of clarity, but I'm reluctant to go further unless we
> get some nifty initdb-caching system.

Hm. From the buildfarm / CF perspective it might still be a win, because the
different pieces can run concurrently. But it's not great :(.

Maybe we really should do at least the most simplistic caching for initdbs, by
doing one initdb as part of the creation of temp_install. Then Cluster::init
would need logic to only use that if $params{extra} is empty.

Greetings,

Andres Freund