We continue to investigate cluster reboots and degraded performance for Redshift RA3 Clusters in the US-EAST-1 Region. The cluster reboots are being triggered by writes that are being impacted by the elevated S3 put latencies. Redshift attempts to retry these writes automatically but if they are unsuccessful after extended attempts, the cluster may restart. If you are able to pause write workloads while we work towards resolving the S3 put latency issue, your clusters will no longer restart and can serve read queries normally.