This topic describes the specifications of persistent memory-optimized instances of ApsaraDB for Redis Enhanced Edition (Tair), including the instances in the standard or cluster architecture. These specifications include the memory capacity, maximum number of connections, and maximum bandwidth.

Purchase an instance

Create a persistent memory-optimized or storage-optimized instance of ApsaraDB for Redis Enhanced Edition (Tair)

Terms

persistent memory-optimized instance
Persistent memory-optimized instances adopt Intel® Optane™ DC persistent memory (AEP) to provide you with in-memory databases that have a large capacity and are compatible with open source Redis. A persistent memory-optimized instance does not use disks to implement data persistence. Compared with an ApsaraDB for Redis Community Edition instance, it reduces costs by up to 30% and provides almost the same performance in terms of throughput and latency. It ensures the persistence of operations and helps improve the reliability of business data. For more information, see Persistent memory-optimized instances.
ESSD
Enhanced SSDs (ESSDs) are disks provided by Alibaba Cloud. For more information about the terms and performance levels of ESSDs, see ESSDs.
Note ESSDs are used only to store system operating data, such as logs, and backup data and are not used as the media to read or write data.

Performance

The specifications described in this topic apply to persistent memory-optimized instances in the standard or cluster architecture. For more information about the standard architecture and the cluster architecture, see Standard master-replica instances and Cluster master-replica instances.

Architecture Performance
Standard The overall performance of standard instances is as described in the instance specifications table.
Cluster The overall performance of cluster instances is calculated by using the following formula: Overall performance of an instance = Number of shards in the instance × Performance of each shard specified by instance specifications. For example, a cluster instance has four shards of the tair.scm.standard.4m.32d type, which is the first instance type in Instance specifications. The following items show the performance of each shard:
  • CPU cores: 6 cores
  • Bandwidth: 96 Mbit/s
  • Maximum number of connections: 30,000

The following items show the overall performance of the cluster instance:

  • CPU cores: 24 cores
  • Bandwidth: 384 Mbit/s
  • Maximum number of connections: 120,000

Instance specifications

Instance type InstanceClass value (used in API operations) Specification Maximum number of connections Maximum bandwidth value (Mbit/s)
Number of CPU cores Persistent memory (GB)
Master-replica 8 GB persistent memory tair.scm.standard.2m.8d 6 8 30,000 96
Master-replica 32 GB persistent memory tair.scm.standard.4m.32d 6 32 30,000 96
Master-replica 32 GB persistent memory tair.scm.standard.8m.32d 6 32 30,000 96
Master-replica 64 GB persistent memory tair.scm.standard.16m.64d 6 64 30,000 96

Notes about CPU cores

To ensure service stability, the system reserves a CPU core to process background tasks. In a cluster instance or a read/write splitting instance, the system reserves a CPU core for each data shard or each read replica to process background tasks.