Migrating as soon as node downtime? Restart node is a heavy work?

Aerospike Enterprise has Fast Restart and Rapid Rebalace. These allow a node to restart and fully migrate data in minutes rather than hours.

A migration tuning guide can be found here: Tuning of migrate-sleep - Setting the migrate-sleep value on the recipient side has no effect.

A feature comparison of Enterprise and Community can be found at Database Features and Editions | Aerospike.