Re: Differential Code Coverage report for Postgres

Thanks for working on this!

On 2025-Sep-05, Nazir Bilal Yavuz wrote:

> 1- One Github Actions run takes ~50 minutes for now and since this
> runs daily it is ~1500 minutes in total for a month. If you include
> manual triggers and failures, it is more than 1500 minutes. Github
> allows 2000 minutes free usage of Github Actions for a month. So, if
> we increase the time (by generating another report), then it may
> exceed the free usage limit. Right now, I install Postgres
> dependencies on each task; I will work on it to reduce time.

I think the goal should be to run this on the pginfra machines. I
wasn't really thinking about doing this until pginfra upgraded to Debian
trixie, because that would have the lcov version we need; but since you
also seem to be cloning lcov, maybe we do that also in pginfra and thus
we could do it right away. Such a machine can use all the CPU time it
needs. (In fact, in a totally overkill approach, we currently run the
report every four hours or something like that. It's easy to run once
or twice daily and run all branches instead.)

> 2- If we want to show both reports on the same page, then it may
> require a bit of HTML coding. I have no experience on that but I do
> not think it will be hard.

I think it's enough to have multiple reports available and a link to
each.

I see that the report shows 7, 30, 360 days of change. I wonder how
that works, and how can we best make use of that. Are you supposed to
run the tests every day and then run the diff with the tests from one
week, one month, one year ago? Or is the script running the test for
7, 30, 360 days ago every time and comparing those with the current one?

Maybe what we want is not "x days ago" but instead compare current
branch HEAD with each previous minor release (up to the merge-base with
master). Does genhtml let you do that? If not, "X days ago" is
probably good enough.

--
Álvaro Herrera PostgreSQL Developer — https://www.EnterpriseDB.com/