Dynamic Stream Filtering

Saving in the editor updates the CloudWatch Metric Stream's IncludeFilters to stream only subscribed namespaces. This minimizes Firehose and S3 costs — you stream exactly what you monitor, and nothing more.

Behavior

• Adding the first subscription in a namespace starts streaming that namespace.
• Removing the last subscription in a namespace stops it.
• Zero subscriptions means the stream is paused entirely — no Firehose or S3 costs when idle.

This keeps ingestion cost proportional to what you actually monitor, with no manual stream management.