Tair Redis OSS-compatible instance specifications and FAQ - Tair (Redis® OSS-Compatible)

Redis Open-Source Edition

References for instance specifications	Description
Redis Open-Source Edition cloud native instances	Standard architecture: up to 64 GB of memory and approximately 100,000 QPS. Read/write splitting architecture: up to 64 GB of memory and approximately 600,000 QPS. Cluster architecture: up to 16,384 GB (64 GB × 256 shards) of memory. Overall performance = number of shards × performance per shard, determined by shard specifications.
Redis Open-Source Edition classic instances	Standard multi-replica instances use the master-replica architecture, with up to 64 GB of memory and approximately 80,000 QPS (reference value). Cluster master-replica instances: each shard uses the master-replica architecture. Up to 4,096 GB (16 GB × 256 shards) of memory and approximately 25,600,000 QPS (reference value). Read/write splitting instances consist of a master node and read replicas, with up to 64 GB of memory and approximately 600,000 QPS.
Retired instance types	Tair (Redis OSS-compatible) specific instance types are no longer available for purchase but remain usable. For specifications such as maximum connections, bandwidth, and QPS, see Retired instance types.

Tair (Enterprise Edition)

References for instance specifications	Description
Memory-optimized instance specifications	DRAM-based instances use a multi-threaded model, delivering approximately 3x the read/write performance of a same-spec Redis Open-Source Edition instance. Standard architecture: up to 64 GB of memory and approximately 300,000 QPS. Read/write splitting architecture: up to 64 GB of memory and approximately 1,800,000 QPS. Cluster architecture: up to 16,384 GB (64 GB × 256 shards) of memory. Overall performance = number of shards × performance per shard, determined by shard specifications. DRAM-based instances also support the classic deployment mode. Standard master-replica architecture: multi-threaded, approximately 3x the performance of a same-spec Redis Open-Source Edition instance. Up to 64 GB of memory and approximately 240,000 QPS. Read/write splitting architecture: multi-threaded, with a master node and read replicas. Approximately 3x the performance of a same-spec Redis Open-Source Edition instance. Up to 64 GB of memory and approximately 1,440,000 QPS. Cluster architecture: multi-threaded, approximately 3x the performance of a same-spec Redis Open-Source Edition instance. Each shard uses master-replica architecture. Up to 4,096 GB (16 GB × 256 shards) of memory and approximately 61,440,000 QPS (reference value).
Persistent memory-optimized instance specifications	Persistent memory-optimized instances persist data without disks, delivering near-identical throughput and latency to Redis Open-Source Edition instances while persisting each operation. Standard instances offer up to 30% cost savings over Redis Open-Source Edition. Standard architecture: up to 64 GB of memory and approximately 100,000 QPS. Read/write splitting architecture: up to 64 GB of memory and approximately 600,000 QPS. Cluster architecture: up to 16,384 GB (64 GB × 256 shards) of memory. Overall performance = number of shards × performance per shard, determined by shard specifications.
Disk-based instance types	ESSD/SSD-based instances store data on disks with memory-accelerated caching, reducing costs by up to 85% compared with Redis Open-Source Edition at approximately 60% of the performance of Redis Open-Source Edition. Suitable for warm and cold data scenarios requiring Redis compatibility, large capacity, and high performance. Up to 32,768 GB (128 GB × 256 shards) of memory and 327,680 GB (1,280 GB × 256 shards) of standard storage.

FAQ

Do I need to reserve memory for snapshots?

No. Redis Open-Source Edition and Tair (Enterprise Edition) instances require no snapshot memory reservation. The listed memory capacity is fully available and includes user data, instance overhead, and network connections.
What happens if QPS exceeds the specification maximum?

QPS reference values are guidelines, not hard limits. Monitor CPU utilization and bandwidth usage — exceeding thresholds may affect service availability.

Note
QPS values in the specification tables are measured with simple GET/SET commands using 16-byte data. Actual QPS depends on command complexity, request size, and access patterns. Run stress tests for your workloads and review the performance whitepaper.
Why is a specific specification type unavailable?

The specification type may be phased out. For more information, see Retired instance types.
How do I look up specifications by instance class?

Enter the instance class in the search box at the top of the Alibaba Cloud documentation page.
How do I test the performance of Tair instances?

You can test the performance of Tair instances using the methods in the Performance whitepaper.
Can I query the number of CPU cores of an instance by calling the DescribeInstances operation?

No. The response of the DescribeInstances operation does not include CPU core counts. To check the number of CPU cores for each instance specification, see the instance specification tables in this topic.