add panel Query Concurrency to dashboard mixin.

[raptorsun]

• I added CHANGELOG entry for this change.
• Change is not relevant to the end user.

Changes

add a panel "Query Concurrency" to the dashboard mixin, showing the available capacity to serve concurrent queries.

Verification

add the dashboard to grafana to check it.

The panel should look like this:

[raptorsun]

how to rerun the failing test? it seems like a transient error.

[fpetkovski]

Suggested change

	"expr": "max_over_time(thanos_query_concurrent_gate_queries_max{job=~\"$job\"}[5m]) - avg_over_time(thanos_query_concurrent_gate_queries_in_flight{job=~\"$job\"}[5m])",
	"expr": "max_over_time(thanos_query_concurrent_gate_queries_max{job=~\"$job\"}[$__rate_interval]) - avg_over_time(thanos_query_concurrent_gate_queries_in_flight{job=~\"$job\"}[$__rate_interval])",

[raptorsun]

Thank you, Filip :) The PR has been updated accordingly.
In the same file there is a variable $interval. Is it equivalent to $__rate_interval ?

[douglascamata]

Hey @raptorsun, can you have a look at the feedback so that we can proceed with merging your contribution, please? 🙏

To rerun the build in case it fails, you can push an empty commit. Here's how you can create an empty commit: git commit -s --allow-empty -m "Empty commit to trigger CI"

[douglascamata]

Small tip: maybe rebasing with main can help reducing the random failures. We've been working on this recently.

[raptorsun]

Small tip: maybe rebasing with main can help reducing the random failures. We've been working on this recently.

The PR has been rebased on latest main branch now.

[douglascamata]

LGTM 💪

Thanks, @raptorsun!

[matej-g]

Seems like this was forgotten, but looks good! Thanks!