We have recently set up our Temporal clusters and are successfully running some production workload on them. Unfortunately, we might have set
numHistoryShards for those clusters too high and are plagued with heavy DB load that doesn’t match the scale of workflows we run.
numHistoryShards cannot be changed after the cluster is deployed, we’ll have to create a new cluster and somehow migrate to it. I wonder if there are some hints or best practices for that? Ideally, we’d like to make the migration without a downtime, but we can also temporarily pause all workflows/signals if that helps the migration. Is there a way to migrate to a different cluster without having to run both side-by-side for a prolonged period of time?