AWS Backup for Amazon S3 now improves the speed of backups by up to 10x for buckets with more than 300 million objects. This performance improvement enables you to speed up your initial S3 backup workflow and back up buckets with more than 3 billion objects. AWS Backup is a policy-based, fully managed and cost-effective solution that enables you to centralize and automate data protection of Amazon S3 along with other AWS services (spanning compute, storage, and databases) and third-party applications. The performance improvement is automatically enabled at no additional cost in all Regions where AWS Backup support for Amazon S3 is available.
Source:: Amazon AWS