It looks like custom metrics will be kept for 15 months, if I understand it correctly, since they get aggregated to higher resolution, according to https://aws.amazon.com/cloudwatch/faqs. Does it mean we have to pay for at least 15 months once we create a custom metric?
I have CloudWatch agent installed to collect various metrics using user_data. It creates new metrics for every new instances. After running many tests, I have more than 6,000 custom metrics, but most of them are unused. Since there is no way to delete custom metrics, do I get charged for those unused metrics until they expire (15 months)? I hope I'm wrong on this :]
Please clarify how we get charged for unused custom metrics.