Re: Serious doubts about Gitlab CI

[Andrew Jones]

On Fri, Mar 19, 2021 at 09:33:43AM +0000, Stefan Hajnoczi wrote:
> On Thu, Mar 18, 2021 at 09:30:41PM +0100, Paolo Bonzini wrote:
> > On 18/03/21 20:46, Stefan Hajnoczi wrote:
> > > The QEMU Project has 50,000 minutes of GitLab CI quota. Let's enable
> > > GitLab Merge Requests so that anyone can submit a merge request and get
> > > CI coverage.
> > 
> > Each merge request consumes about 2500.  That won't last long.
> 
> Yikes, that is 41 hours per CI run. I wonder if GitLab's CI minutes are
> on slow machines or if we'll hit the same issue with dedicated runners.
> It seems like CI optimization will be necessary...
>

We need to reduce the amount of CI we do, not only because we can't afford
it, but because it's wasteful. I hate to think of all the kWhs spent
testing the exact same code in the exact same way, since everyone runs
everything with a simple 'git push'. IMHO, 'git push' shouldn't trigger
anything. Starting CI should be an explicit step. Also, the default CI
should only trigger tests associated with the code changed. One should
have to explicitly trigger a complete CI when they deem it worthwhile.

Do we already have some sort of CI limiters? Or is anybody looking at
that for QEMU? Are people aware of other projects that try to limit
their CI and how they do it?

Thanks,
drew