2th of 4 Questions.
What changed in Redis 6 regarding threading?
Redis 6 introduced threaded I/O — multiple threads handle reading from and writing to network sockets concurrently. However, command execution still happens on the main thread serially. This improves throughput on high-connection, large-payload workloads without breaking the atomicity guarantee of command execution. Enable with io-threads 4 (match to CPU cores, not exceed them).