How to monitor Redis performance metrics

Redis is a popular in-memory key/value data store used across industries and use cases such as databases, message queues, and memory caches. Monitoring Redis can help detect resource issues with the database itself or problems arising elsewhere in supporting infrastructure. Key performance metrics include latency, instantaneous_ops_per_sec, hit rate, used_memory, mem_fragmentation_ratio, evicted_keys, blocked_clients, connected_clients, connected_slaves, master_last_io_seconds_ago, keyspace, rdb_last_save_time, and rdb_changes_since_last_save. Error metrics include rejected_connections, keyspace_misses, and master_link_down_since_seconds. Monitoring these metrics can provide good visibility into the health and performance of Redis servers.