Incorrectly calculated runner count from jobs, causes increased Queued time

[strowk]

Checks

• I've already read https://docs.github.com/en/actions/hosting-your-own-runners/managing-self-hosted-runners-with-actions-runner-controller/troubleshooting-actions-runner-controller-errors and I'm sure my issue is not covered in the troubleshooting guide.
• I am using charts that are officially provided

Controller Version

0.12.0

Deployment Method

Helm

Checks

• This isn't a question or user support case (For Q&A and community support, go to Discussions).
• I've read the Changelog before submitting this issue and I'm sure it's not due to any recently-introduced backward-incompatible changes

To Reproduce

0. Configure runner set with max amount of runners > 1
1. Create Github workflow and push two commits in the same branch
2. Notice that two workflow runs are created, but only one starts
3. Check controller logs, showing this : `Calculated target runner count    {"assigned job": 0, "decision": 1, "min": 0, "max": 4,`

Describe the bug

Only one ephemeral runner is created. Second job is stuck in Queued until first one is finished.

Describe the expected behavior

Expectation is that in this case controller would decide to run 2 runners, not only 1.

Additional Context

I did not configure anything that would limit amount of runners per branch and I don't think this had behaved like this before, so it seems like recent degradation.
I tried restarting both controller and listener, this does not fix the issue, second workflow run was still waiting for until the first one was done.

Controller Logs

2025-08-27T12:56:45Z	INFO	EphemeralRunnerSet	Ephemeral runner counts	{"version": "0.12.0", "ephemeralrunnerset": {"name":"linux-arm64-selfhosted-g6pbp","namespace":"github-arc-private-runner"}, "pending": 0, "running": 1, "finished": 0, "failed": 0, "deleting": 0}
2025-08-27T12:56:45Z	INFO	EphemeralRunnerSet	Scaling comparison	{"version": "0.12.0", "ephemeralrunnerset": {"name":"linux-arm64-selfhosted-g6pbp","namespace":"github-arc-private-runner"}, "current": 1, "desired": 1}
2025-08-27T12:57:35Z	INFO	EphemeralRunnerSet	Ephemeral runner counts	{"version": "0.12.0", "ephemeralrunnerset": {"name":"linux-arm64-selfhosted-g6pbp","namespace":"github-arc-private-runner"}, "pending": 0, "running": 1, "finished": 0, "failed": 0, "deleting": 0}
2025-08-27T12:57:35Z	INFO	EphemeralRunnerSet	Scaling comparison	{"version": "0.12.0", "ephemeralrunnerset": {"name":"linux-arm64-selfhosted-g6pbp","namespace":"github-arc-private-runner"}, "current": 1, "desired": 1}
2025-08-27T12:57:35Z	INFO	AutoscalingRunnerSet	Find existing ephemeral runner set	{"version": "0.12.0", "autoscalingrunnerset": {"name":"linux-arm64-selfhosted","namespace":"github-arc-private-runner"}, "name": "linux-arm64-selfhosted-g6pbp", "specHash": "6d4c5855dc"}
2025-08-27T12:58:26Z	INFO	AutoscalingRunnerSet	Find existing ephemeral runner set	{"version": "0.12.0", "autoscalingrunnerset": {"name":"linux-arm64-selfhosted","namespace":"github-arc-private-runner"}, "name": "linux-arm64-selfhosted-g6pbp", "specHash": "6d4c5855dc"}
2025-08-27T12:58:26Z	INFO	EphemeralRunnerSet	Ephemeral runner counts	{"version": "0.12.0", "ephemeralrunnerset": {"name":"linux-arm64-selfhosted-g6pbp","namespace":"github-arc-private-runner"}, "pending": 0, "running": 1, "finished": 0, "failed": 0, "deleting": 0}
2025-08-27T12:58:26Z	INFO	EphemeralRunnerSet	Scaling comparison	{"version": "0.12.0", "ephemeralrunnerset": {"name":"linux-arm64-selfhosted-g6pbp","namespace":"github-arc-private-runner"}, "current": 1, "desired": 1}
2025-08-27T12:59:16Z	INFO	AutoscalingRunnerSet	Find existing ephemeral runner set	{"version": "0.12.0", "autoscalingrunnerset": {"name":"linux-arm64-selfhosted","namespace":"github-arc-private-runner"}, "name": "linux-arm64-selfhosted-g6pbp", "specHash": "6d4c5855dc"}
2025-08-27T12:59:16Z	INFO	EphemeralRunnerSet	Ephemeral runner counts	{"version": "0.12.0", "ephemeralrunnerset": {"name":"linux-arm64-selfhosted-g6pbp","namespace":"github-arc-private-runner"}, "pending": 0, "running": 1, "finished": 0, "failed": 0, "deleting": 0}
2025-08-27T12:59:16Z	INFO	EphemeralRunnerSet	Scaling comparison	{"version": "0.12.0", "ephemeralrunnerset": {"name":"linux-arm64-selfhosted-g6pbp","namespace":"github-arc-private-runner"}, "current": 1, "desired": 1}
2025-08-27T13:00:06Z	INFO	EphemeralRunnerSet	Ephemeral runner counts	{"version": "0.12.0", "ephemeralrunnerset": {"name":"linux-arm64-selfhosted-g6pbp","namespace":"github-arc-private-runner"}, "pending": 0, "running": 1, "finished": 0, "failed": 0, "deleting": 0}
2025-08-27T13:00:06Z	INFO	EphemeralRunnerSet	Scaling comparison	{"version": "0.12.0", "ephemeralrunnerset": {"name":"linux-arm64-selfhosted-g6pbp","namespace":"github-arc-private-runner"}, "current": 1, "desired": 1}
2025-08-27T13:00:06Z	INFO	AutoscalingRunnerSet	Find existing ephemeral runner set	{"version": "0.12.0", "autoscalingrunnerset": {"name":"linux-arm64-selfhosted","namespace":"github-arc-private-runner"}, "name": "linux-arm64-selfhosted-g6pbp", "specHash": "6d4c5855dc"}
2025-08-27T13:00:56Z	INFO	AutoscalingRunnerSet	Find existing ephemeral runner set	{"version": "0.12.0", "autoscalingrunnerset": {"name":"linux-arm64-selfhosted","namespace":"github-arc-private-runner"}, "name": "linux-arm64-selfhosted-g6pbp", "specHash": "6d4c5855dc"}
2025-08-27T13:00:56Z	INFO	EphemeralRunnerSet	Ephemeral runner counts	{"version": "0.12.0", "ephemeralrunnerset": {"name":"linux-arm64-selfhosted-g6pbp","namespace":"github-arc-private-runner"}, "pending": 0, "running": 1, "finished": 0, "failed": 0, "deleting": 0}
2025-08-27T13:00:56Z	INFO	EphemeralRunnerSet	Scaling comparison	{"version": "0.12.0", "ephemeralrunnerset": {"name":"linux-arm64-selfhosted-g6pbp","namespace":"github-arc-private-runner"}, "current": 1, "desired": 1}

Runner Pod Logs

These are not captured in my deployment

[air-hand]

I did not configure anything that would limit amount of runners per branch and I don't think this had behaved like this before, so it seems like recent degradation.
I tried restarting both controller and listener, this does not fix the issue, second workflow run was still waiting for until the first one was done.

That's strange... Of course, you're not using concurrency in the workflow, right?
If you use a GitHub-hosted runner like ubuntu-latest in the same workflow, it doesn't happen, does it?
I want to know the minimum reproducible workflow.

[strowk]

Of course, you're not using concurrency in the workflow, right?

Nope, nothing like that is used

If you use a GitHub-hosted runner like ubuntu-latest in the same workflow, it doesn't happen, does it?

Can't say, the workflow won't work outside of self-hosted ARC, as it requires some stuff for security that is not provided for shared runners yet