[cfarm-users] Setting up GitLab CI for git.git on the farm

[Segher Boessenkool]

Hi!

On Sat, Nov 24, 2018 at 11:28:58PM +0100, Ævar Arnfjörð Bjarmason via cfarm-users wrote:
> I got access to the farm a while ago to test free software projects I
> work on, mainly git.git. I wanted to send a headsup about what I've been
> up to.
> 
> I'm setting up something where the integration branches of git.git are
> smoke tested on various machines on the farm. See the Git ML
> announcement at
> https://public-inbox.org/git/875zwm15k2.fsf@evledraar.gmail.com/
> 
> Currently I'm running things on these machines:
> https://gitlab.com/git-vcs/git-gitlab-ci/blob/b8d4645891aa/.gitlab-ci.yml#L16-57
> 
> I've tried to be conservative about resources. It's all nice -n 19'd,
> and with a conservative -j value relative to the number of cores:
> https://gitlab.com/git-vcs/git-gitlab-ci/blob/b8d4645891aa/ci/gitlab/run-on-gcc-farm.sh#L62-163

At least for the Power machines, that isn't conservative at all.
-j1 is conservative.  -j24 is not conservative on a machine with 20 CPUs
(gcc112), or 32 CPUs (gcc135).  The AIX (gcc119) jobs seem to run for over
an hour on half the machine?  That's no good :-(

There are two important considerations for automated jobs.  Are things set
up so that your task cannot monopolise a system; and, are things set up so
that your automated tasks do not hinder interactive work.

Could you please work on making those two things true?


Segher