Amazon Managed Blockchain now supports Amazon CloudWatch metrics for peer nodes. You can view CPU and memory utilization of your peer nodes which gives insight into peer node performance. You can also view the transaction rate for each network channel on a peer node. Transaction rate can help you optimize network performance and transaction configuration settings. Additionally, CloudWatch metrics enable you to set alarms or automate actions based on predefined thresholds and easily build dashboards that overlay different metrics. 

from Recent Announcements https://aws.amazon.com/about-aws/whats-new/2019/10/amazon-managed-blockchain-supports-amazon-cloudwatch-metrics-for-peer-nodes/