This topic describes the specifications of master-replica cluster instances of ApsaraDB for Redis Community Edition. These specifications include the memory capacity, number of concurrent connections to each instance, maximum internal bandwidth, and queries per second (QPS) reference value.

Instance specifications

Specification InstanceClass (used in API operations) Number of shards Maximum number of new connections per second Maximum number of connections Bandwidth (Mbit/s) QPS reference value
16 GB cluster instance redis.logic.sharding.2g.8db.0rodb.8proxy.default 8 50000 80000 768 640000
32 GB cluster instance redis.logic.sharding.4g.8db.0rodb.8proxy.default 8 50000 80000 768 640000
64 GB cluster instance redis.logic.sharding.8g.8db.0rodb.8proxy.default 8 50000 80000 768 640000
128 GB cluster instance redis.logic.sharding.8g.16db.0rodb.16proxy.default 16 50000 160000 1536 1280000
256 GB cluster instance redis.logic.sharding.16g.16db.0rodb.16proxy.default 16 50000 160000 1536 1280000
512 GB cluster instance redis.logic.sharding.16g.32db.0rodb.32proxy.default 32 50000 320000 2048 2560000

Calculation rules for bandwidth values

  • The bandwidth in the preceding tables refers to the bandwidth of the instance. It is the sum of the bandwidth of all shards or nodes on the instance. Each shard has the following bandwidth limits:
    • Community Edition: If the memory of each shard is less than or equal to 1 GB, the maximum bandwidth of each shard is 48 Mbit/s. If the memory of each shard is greater than 1 GB, the maximum bandwidth of each shard is 96 Mbit/s.
    • Enhanced Edition (Tair): The maximum bandwidth of each shard is 96 Mbit/s.
  • When the default proxy endpoint is used by a cluster instance, the upper limit of bandwidth for the cluster instance is 2,048 Mbit/s. After the upper limit is reached, the bandwidth cannot be increased even if more shards are configured.
    Note To handle excessive network traffic for your business, you can enable the direct connect mode. For more information, see Enable the direct connect mode (applicable to only cluster instances). In direct connect mode, the upper limit of bandwidth equals the maximum bandwidth of a single shard multiplied by the number of shards. For example, for a cluster instance with 128 shards (each shard is allocated with a memory of more than 1 GB), the bandwidth limit is 12,288 Mbit/s.
  • The bandwidth value is applicable to the upstream bandwidth and the downstream bandwidth. If the bandwidth of an instance is 10 Mbit/s, the upstream and downstream bandwidth of the instance are both 10 Mbit/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 connect to the instance over an internal network to maximize the performance.

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 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 (12,000 + 10,000).
  • The maximum number of new connections per second and the maximum number of connections in the preceding table both refer to the total number of connections of the instance in proxy mode. The maximum number of connections is 500,000 or less. After the value is reached, the maximum number of connections is not increased even if the number of shards or nodes is increased.
    Note If you enable direct connection for a cluster instance, the connectivity performance of the instance degrades because the proxy node is bypassed. For cluster instances of Community Edition, the maximum number of connections for a single shard is 10,000, and the maximum number of new connections per second is 2,000. For cluster instances of Enhanced Edition, the maximum number of connections for an individual shard is 30,000, the maximum number of new connections per second is 2,000.

FAQ

Q: Why is the actual bandwidth of my instance different from the bandwidth described in this topic?

A: The bandwidth of some instance types may be adjusted after they are upgraded. If the bandwidth of your instance is different from what is described in this topic, you can change configurations to upgrade the bandwidth of your instance. You are not charged if you select the same specifications for your instance.