Read/write splitting instances of ApsaraDB for Redis are classified into non-cluster read/write splitting instances and read/write splitting cluster instances. The limits on these supported commands vary based on different instance types.
| Architecture | Description | Limits |
|---|---|---|
| Non-cluster read/write splitting instance | A non-cluster read/write splitting instance is a single-shard read/write splitting instance. The architecture consists of one read/write shard and one, three, or five read replicas. The read/write shard runs in a master-replica structure. | The instance supports the commands that are supported by standard instances of ApsaraDB for Redis. For more information, see Commands supported by Community Edition. |
| Read/write splitting cluster instance | A read/write splitting cluster instance consists of multiple read/write shards. Each shard runs in a master-replica structure and has one read replica attached. | The instance supports the commands that are supported by cluster instances of ApsaraDB for Redis. For more information, see Limits on the commands supported by cluster instances. |
To simplify operations and maintenance, cluster and read/write splitting instances support multiple commands that are developed by Alibaba Cloud. For more information, see Redis commands developed by Alibaba Cloud.