Architecture

An ApsaraDB for Redis instance of the master-replica cluster edition consists of a configuration server, proxy servers, and shard servers.

  • The configuration server acts as a cluster management tool that runs in a master-replica architecture. It stores cluster configuration information and partition policies.
  • A proxy server runs in a single-node architecture. A cluster has multiple proxy servers. The cluster automatically balances loads and performs failover among these proxy servers.
  • A shard server runs in a master-replica architecture. If the master node fails, a failover is triggered so that the replica node takes over services. This guarantees high availability of services.

An ApsaraDB for Redis instance of the master-replica cluster edition provides a domain name for clients to access the instance. You can use the domain name to access the ApsaraDB for Redis instance and operate data stored on the instance. You cannot access the configuration server, proxy servers, or shard servers directly.

A client connects to the proxy servers through Server Load Balancer (SLB) and accesses the shard servers through the proxy servers. The following figure shows the architecture of an ApsaraDB for Redis instance of the master-replica cluster edition.

Region and zone

All tests are performed in zone E of the China (Hangzhou) region.

ECS instance configurations

In the test environment, the configurations of the Elastic Compute Service (ECS) instances vary with the type of the ApsaraDB for Redis instance that is tested. Take the 128 GB cluster and the 64 GB cluster types for example.

The configurations of the ECS instances used for testing the ApsaraDB for Redis instance of the 128 GB cluster type are as follows:

  • Ten ECS instances, each of which has 4 vCPUs and 8 GB memory
  • Four ECS instances, each of which has 12 vCPUs and 48 GB memory
  • Network type: Virtual Private Cloud (VPC)
  • Operating system: CentOS 6.0, 64-bit

The configurations of the ECS instances used for testing the ApsaraDB for Redis instance of the 64 GB cluster type are as follows:

  • Ten ECS instances, each of which has 4 vCPUs and 8 GB memory
  • Network type: VPC
  • Operating system: CentOS 6.0, 64-bit

ApsaraDB for Redis instance configuration

  • The configurations of the ApsaraDB for Redis instances depend on the instance type.
  • This white paper uses ApsaraDB for Redis 2.8 instances for benchmark testing. The test result for ApsaraDB for Redis 4.0 instances is similar to that for ApsaraDB for Redis 2.8 instances.