Instance specifications - Tair (Redis® OSS-Compatible) - Alibaba Cloud Documentation Center

Tair (Redis OSS-compatible) provides multiple editions, series types, and architectures. This topic helps you find the references about the specifications of different instances.

Redis Open-Source Edition

References for instance specifications	Description

References for instance specifications	Description
Specifications of Redis Open-Source Edition cloud-native instances	If an instance uses the standard architecture, the instance provides up to 64 GB of memory and supports up to approximately 100,000 queries per second (QPS). If an instance uses the read/write splitting architecture, the instance provides up to 64 GB of memory and supports up to approximately 600,000 QPS. If an instance uses the cluster architecture, the instance provides up to 16,384 GB (64 GB × 256 shards) of memory. The overall performance of the instance is calculated by using the following formula: Number of shards × Performance per shard. The performance of each shard is determined by the shard specifications.
Specifications of Redis Open-Source Edition classic instances	A standard master-replica instance is deployed in the master-replica architecture. Each instance provides up to 64 GB of memory and supports up to approximately 80,000 QPS. This maximum QPS value is for reference only. For a cluster master-replica instance, each data shard is deployed in the master-replica architecture. Each instance provides up to 4,096 GB (16 GB × 256 shards) of memory and supports up to approximately 25,600,000 QPS. This maximum QPS value is for reference only. A read/write splitting instance consists of a master node and one or more read replicas. Each instance provides up to 64 GB of memory and supports up to approximately 600,000 QPS.
Retired instance types	Tair (Redis OSS-compatible) instances of specific specification types are no longer available. If you have purchased one or more of these instances, you can continue to use them. For information about the specifications of these instances, such as the maximum number of connections, maximum bandwidth, and QPS reference value, see Retired instance types.

Tair (Enterprise Edition)

References for instance specifications	Description

References for instance specifications	Description
DRAM-based instances	DRAM-based instances use a multi-threaded model. A DRAM-based instance provides approximately three times the read and write performance of a Redis Open-Source Edition instance that has the same specifications. If the instance uses the standard architecture, the instance provides up to 64 GB of memory and supports up to approximately 300,000 QPS. If the instance uses the read/write splitting architecture, the instance provides up to 64 GB of memory and supports up to approximately 1,800,000 QPS. If an instance uses the cluster architecture, the instance provides up to 16,384 GB (64 GB × 256 shards) of memory. The overall performance of the instance is calculated by using the following formula: Number of shards × Performance per shard. The performance of each shard is determined by the shard specifications. DRAM-based instances also support the classic deployment mode. Standard master-replica architecture: uses a multi-threaded model and provides approximately three times the performance of a Redis Open-Source Edition instance that has the same specifications. Each instance provides up to 64 GB of memory and supports up to approximately 240,000 QPS. Read/write splitting architecture: uses a multi-threaded model, runs in the master-replica architecture, and consists of a master node and one or more read replicas. A read/writing splitting instance provides approximately three times the performance of a Redis Open-Source Edition instance that has the same specifications. Each instance provides up to 64 GB of memory and supports up to approximately 1,440,000 QPS. Cluster architecture: uses a multi-threaded model and provides approximately three times the performance of a Redis Open-Source Edition instance that has the same specifications. Each data shard uses the master-replica architecture. Each instance provides up to 4,096 GB (16 GB × 256 shards) of memory and supports up to approximately 61,440,000 QPS. This maximum QPS value is for reference only.
Persistent memory-optimized instances	Persistent memory-optimized instances do not use disks to implement data persistence. A persistent memory-optimized instance provides almost the same performance as a Redis Open-Source Edition instance in terms of throughput and latency while persisting each operation. A standard persistent memory-optimized instance can offer up to 30% cost reduction compared with a Redis Open-Source Edition instance. If the instance uses the standard architecture, the instance provides up to 64 GB of memory and supports up to approximately 100,000 QPS. If the instance uses the read/write splitting architecture, the instance provides up to 64 GB of memory and supports up to approximately 600,000 QPS. If the instance uses the cluster architecture, the instance provides up to 16,384 GB of memory (64 GB × 256 shards). The overall performance of the instance is calculated by using the following formula: Number of shards × Performance per shard. The performance of each shard is determined by the shard specifications.
ESSD/SSD-based instances	ESSD/SSD-based instances store all data in disks and use memory to accelerate caching. ESSD/SSD-based instances reduce up to 85% of costs compared with Redis Open-Source Edition instances, and deliver approximately 60% of the performance of Redis Open-Source Edition instances. ESSD/SSD-based instances are suitable for warm and cold data storage scenarios that require compatibility with open source Redis, large capacity, and high access performance. Each instance provides up to 32,768 GB (128 GB × 256 shards) of memory and has a standard storage capacity of up to 327,680 GB (1,280 GB × 256 shards).

FAQ

Do I need to reserve memory for snapshots when I select specifications?
No. Redis Open-Source Edition and Tair (Enterprise Edition) are sold in the form of instances. You do not need to reserve memory for snapshots. The memory capacity of each specification type is the maximum memory that is available to you. The memory capacity includes the memory occupied by user data, the static memory consumed by your instance, and the memory occupied by network connections.
Each specification type has a maximum QPS value. What happens if the QPS of an instance exceeds the maximum value?
The QPS reference values are provided merely as a guideline and are not strict limits. We recommend that you monitor metrics such as CPU utilization and bandwidth usage. If any of these metrics reach their thresholds, the service availability of the instance may be affected.
Note
The QPS reference values in the instance specification tables are measured based on simple commands like GET/SET with 16-byte data. However, in practical use, the QPS of an instance is influenced by factors such as the time complexity of commands, request sizes, and access patterns. For a more comprehensive understanding, refer to the performance whitepaper and the results from stress tests specific to your business scenarios.
Why is a specific specification type unavailable?
The specification type may be phased out. For more information, see Retired instance types.
How do I check the specifications of an instance by using the instance class?
You can enter the instance class in the search box in the upper part of an Alibaba Cloud document to search for the specifications.
How do I test the performance of Tair instances?
You can test the performance of Tair instances by using the methods that are described in the performance whitepaper. For more information, see Performance whitepaper.