What does setting DD_CHECKS_TAG_CARDINALITY=high change compared to DD_CHECKS_TAG_CARDINALITY=low?

Setting DD_CHECKS_TAG_CARDINALITY to high versus low primarily influences the tagging behavior associated with check metrics in Datadog. When the cardinality is set to high, it allows for a greater number of unique tags to be attached to the metrics being collected by checks. This enables users to capture more detailed information and provides richer context for analyses, dashboards, and alerts.

In contrast, setting the cardinality to low limits the number of unique tags that can be attached. This can be beneficial in reducing the overhead associated with managing a large number of unique metrics, but it comes at the cost of potentially losing valuable granularity and insight in the collected data.

Thus, when using a high cardinality setting, the ability to leverage diverse tag combinations enables more comprehensive monitoring and troubleshooting capabilities, which is crucial for nuanced performance tracking and operational visibility in applications and infrastructure.