This topic describes the specifications of read/write splitting cluster instances of ApsaraDB for Redis Community Edition. The specifications include the memory capacity, maximum number of concurrent connections to each instance, maximum bandwidth, and queries per second (QPS) value.

Instance types

Note The following table describes the instance types that contain two shards. For example, 4 GB read/write splitting instance (2 shards, 1 read replica) indicates that the instance has two shards. Each shard contains one read replica.
Instance type InstanceClass that is used in API operations Number of CPU cores Number of shards Number of read replicas per shard Bandwidth (MB/s) Maximum number of new connections per second Maximum number of concurrent connections QPS value
4 GB read/write splitting instance (2 shards, 1 read replica) redis.logic.splitrw.sharding2g.2db.1rodb.4proxy.default 8 2 1 384 40,000 40,000 400,000
8 GB read/write splitting instance (2 shards, 1 read replica) redis.logic.splitrw.sharding4g.2db.1rodb.4proxy.default 8 2 1 384 40,000 40,000 400,000
16 GB read/write splitting instance (2 shards, 1 read replica) redis.logic.splitrw.sharding8g.2db.1rodb.8proxy.default 8 2 1 384 40,000 40,000 400,000
32 GB read/write splitting instance (8 shards, 1 read replica) redis.logic.splitrw.sharding4g.8db.1rodb.16proxy.default 32 8 1 1,536 50,000 160,000 1,600,000
64 GB read/write splitting instance (16 shards, 1 read replica) redis.logic.splitrw.sharding4g.16db.1rodb.32proxy.default 64 16 1 2,048 50,000 320,000 3,200,000
128 GB read/write splitting instance (16 shards, 1 read replica) redis.logic.splitrw.sharding8g.16db.1rodb.32proxy.default 64 16 1 2,048 50,000 320,000 3,200,000
256 GB read/write splitting instance (32 shards, 1 read replica) redis.logic.splitrw.sharding8g.32db.1rodb.64proxy.default 128 32 1 2,048 50,000 500,000 6,400,000
512 GB read/write splitting instance (32 shards, 1 read replica) redis.logic.splitrw.sharding16g.32db.1rodb.64proxy.default 128 32 1 2,048 50,000 500,000 6,400,000

Calculation rules for bandwidth values

  • The bandwidth value in the preceding table is the bandwidth of the instance. The bandwidth value is the sum of the bandwidth of all shards or nodes on the instance.
  • The upper limit of the total bandwidth for a read/write splitting instance is 2,048 MB/s. The preceding table describes the upper limits. After the upper limit is reached, the bandwidth cannot be increased even if you add more shards or nodes.
  • The bandwidth value applies to the upstream and downstream bandwidths. For example, if the bandwidth of an instance is 10 MB/s, the upstream and downstream bandwidths of the instance are both 10 MB/s.
  • The bandwidth in the preceding table is the internal bandwidth of the ApsaraDB for Redis instance. The Internet bandwidth is determined by the internal bandwidth and is limited by the bandwidth of the connection between the instance and a client. We recommend that you use an internal network to maximize the performance of the instance.

Calculation rules for connections

The following example shows the maximum number of new connections that can be created per second: The maximum number of new connections per second of an instance is 10,000. The maximum number of connections of an instance is 50,000. The actual number of connections at the Nth second after the instance starts to run is 12,000. Then, at the (N+1)th second, the number of connections is 22,000, which is calculated by using the formula 12,000 + 10,000.

FAQ

Q: How can I create a read/write splitting cluster instance in the console?

A: To create a read/write splitting cluster instance in the console, perform the following steps:
  1. Log on to the ApsaraDB for Redis console. In the left-side navigation pane, click Instances and click Create Instance. On the buy page, set Architecture Type to Cluster.
  2. Set Shards to the number of shards on the read/write splitting instance.
  3. Set Node Type to Master-Replica.
  4. Select the specifications from the Instance Class drop-down list.