macOS Runners

[ChrisEdson]

Hi there -

Is it possible to support macOS runners using this module?

Technically, GitHub states that it is possible - and AWS also has mac instances that it can spin up.

Thanks!

[npalm]

Indeed, would be great to have support, hopefully the community can help. The catch is the way mac-os instances are billed.

[aheritier]

Do we have some people in the community who studied this topic ?
It's something we will look at in Q4 but not being alone might help cc @tdelaune
Effectively the main challenge is the cost management with the 24h reservation

Billing is per second, with a 24-hour minimum allocation period for the Dedicated Host to comply with the Apple macOS Software License Agreement.

It means that they shouldn't be ephemeral but shared instances which are running for several days in a raw.

I imagine that there are also some challenges to be sure that a user session is opened (starting the host is not enough with an ssh access and some tools require a session to be started).

Any other thing we should keep in mind?

[edersonbrilhante]

I created a PR supporting macos. I am already using in my environment and works fine.

Context:
Mac instances requires a dedicated host.
1 host = 1 instance.

You pay for the Dedicated Host, even if you don't have a instance running in the Dedicated Host. When you request, you pay for 24h of usage, after that you can release or keeping pay per second of usage.

When you terminate an instance, the Dedicated Host goes to a cleanup stage, that about 50 minutes to be available to be used again by another instance. And during this time you don't pay.

It can be possible to use ephemeral runners, just need to handle the errors(scale errors) when a host is already in use or in cleanup stage, so the gh event can be retrigger by control plane.