How Redis Cluster Maintains Availability while Re-Sharding

redis hash slot   Dan redis slot

Hash tags are a way to ensure that multiple keys are allocated in the same hash slot This is used in order to implement multi-key operations in Redis Cluster

The Redis cluster has 16384 hash slots Each key is checked modulo 16384 after CRC16 verification to determine which slot to place Each node in the cluster is But in this example we'll assume they are just ten, from 0 to 9 ;) Different nodes will hold a subset of hash slots A given key foo is at slot: slot = crc16

demo slot fun 4 Redis Cluster key如何存储 Redis Cluster方案采用哈希槽（Hash Slot）来处理数据和实例之间的映射关系。在Redis Cluster方案中，一个切片集群共有 Returns the number of keys in a hash slot