AWS Lambda Adds Enhanced Visibility into Stream-based Processing Operations

You can now monitor and track the time that records spend in Amazon Kinesis and Amazon DynamoDB streams before being processed by your AWS Lambda functions. Using the new IteratorAge metric, you can easily detect delays in stream processing and create alarms that help you efficiently monitor your stream-based operation’s health and performance. The IteratorAge metric is now available as a default metric which is free of charge. It is viewable in the Lambda console’s monitoring tab. 
Quelle: aws.amazon.com