Amazon S3 Access Points customers can now configure Amazon CloudWatch request metrics. With this launch, S3 request metrics can now be generated for all objects in a bucket, or you can generate metrics for specific combinations of prefix, object tags, or access points. With S3 Access Points, you can easily build the right access controls to shared dataset and now with the support of filtering by access points, you can monitor the request patterns by access controls. You can use the S3 Management Console, SDK, API, or AWS CloudFormation to enable S3 request metrics. The metrics are available at 1-minute intervals and can be monitored on both the Amazon S3 Console or on Amazon CloudWatch Console.
Source:: Amazon AWS