Question

A SysOps administrator publishes a high-resolution custom metric to CloudWatch with a storage resolution of 1 second to monitor a latency-sensitive trading application. After two weeks, a colleague reports that when querying the metric over a 90-day period, the 1-second data points are no longer available and only coarser aggregations appear. What is the reason for this behavior?

Accepted Answer

CloudWatch automatically aggregates high-resolution metrics into coarser resolutions over time and retains data for a total of 15 months, but sub-minute data is only kept for 3 hours.

Answer

High-resolution custom metrics are only retained for 3 hours before being deleted entirely from CloudWatch.

Answer

Custom metrics must be re-published with a metric filter to preserve high-resolution data beyond 7 days.

Answer

High-resolution metrics require Detailed Monitoring to be enabled, otherwise all data points are discarded after 24 hours.