Amazon CloudWatch metrics for Amazon S3 can help you understand and improve the performance of applications that use Amazon S3. There are several ways that you can use CloudWatch with Amazon S3.
- Daily storage metrics for buckets ‐ Monitor bucket storage using CloudWatch, which collects and processes storage data from Amazon S3 into readable, daily metrics. These storage metrics for Amazon S3 are reported once per day and are provided to all customers at no additional cost.
- Request metrics ‐ Monitor Amazon S3 requests to quickly identify and act on operational issues. The metrics are available at 1-minute intervals after some latency to process. These CloudWatch metrics are billed at the same rate as the Amazon CloudWatch custom metrics. For information about CloudWatch pricing, see Amazon CloudWatch pricing. To learn how to opt in to getting these metrics, see Metrics Configurations for Buckets.
When enabled, request metrics are reported for all object operations. By default, these 1-minute metrics are available at the Amazon S3 bucket level. You can also define a filter for the metrics collected using a shared prefix or object tag. This allows you to align metrics filters to specific business applications, workflows, or internal organizations. - Replication metrics ‐ Monitor the total number and size of objects that are pending replication, and the maximum replication time to the destination Region. Only replication rules that have S3 Replication Time Control (S3 RTC) enabled will publish replication metrics.
Unlike CloudWatch storage and request metrics, you can’t filter replication metrics by prefixes and tags. However, you can set up a replication rule based on prefixes and tags. Your replication metrics will then monitor replication for the prefixes and tags that you specified. For more information, see Replicating Objects Using S3 Replication Time Control (S3 RTC).