Sometimes Metrics explorer does not show metrics

Hi,

we are running Grafana v10.4.0 in GKE and use Mimir for metrics (using the official Helm charts). Sometimes our users complain about Metrics explorer not showing metrics.

When using Explore or adding a new panel, Metrics explorer sometimes does not show any metrics.

Our Mimir data source is added to all Grafana organizations (we only have “public” metrics shared across all teams).

Depending on what combination of labels was provided, Metrics explorer shows or does not show metrics.

We received this error:

execution: expanding series: the query exceeded the maximum number of chunks (limit: 2000000 chunks) (err-mimir-max-chunks-per-query). To adjust the related per-tenant limit, configure -querier.max-fetched-chunks-per-query, or contact your service administrator

We already increased the max_fetched_chunks_per_query limit in Mimir, but still face the same issue, but without the error message.

Is there any way to tweak Metrics explorer? Maybe a way to enforce a minimum amount of labels to be defined, before Metrics explorer is fetching data?