Note: If you are looking for the Memorystore for Redis Cluster documentation,seeMemorystore for Redis Cluster overview.

This page describes the differences between the available Redis tiers.

Memorystore for Redis supports Basic and StandardTiers. The Basic Tier is best suited for applications that use Redis as a cacheand can withstand a cold restart and full cache flush. Standard Tier instancesprovideHigh Availabilityusing replication, read replicas, and automatic failover.

It is not possible to upgrade from Basic Tier to Standard Tier or the other wayaround. If you want to move data from an existing Basic Tier instance to a newStandard Tier instance, useimport and exportto move your data.

Tier architecture

The following diagrams show the architectures for theMemorystore for Redis service tiers.

Basic Tier

• One Redis node
• Ephemeral cache

Standard Tier

• ProvidesHigh Availabilitywith replication
• Fails over to replica in the case of primary node failure

Standard Tier with read replicas

• ProvidesHigh Availabilitywith replication
• Read replicas allow for distributed reads

Feature comparison

Specifications	Basic Tier	Standard Tier (read replicas disabled)	Standard Tier (read replicas enabled)
Description	Provides a cache with no replication	Provides redundancy and availability using replication	Provides redundancy and availability using replication to backup data, and multiple Read replicas to increase read throughput
Max Redis primary size	300 GB	300 GB	300 GB
Max network bandwidth	16 Gbps	16 Gbps	16 Gbps total for writes. 16 Gbps per node for reads.1
I/O threads	Yes2	Yes2	Yes2
Scale primary size	Yes	Yes	Yes
Scale number of read replicas	No	No	Yes
Cross-zone replication	No	Yes3	Yes3
Automatic failover	No	Yes	Yes
Read replicas	No	No	Yes
In-transit encryption	Yes	Yes	Yes
Maintenance window	Yes	Yes	Yes
Cloud Monitoring	Yes	Yes	Yes

¹The maximum write throughput is 16 Gbps. Read throughput is dependent on the number of nodes (read replicas) in the instance, including the primary node. For example, if you have an instance with 1 primary node and 2 read replicas, the total read throughput is 48 Gbps.

²I/O threads are only available on M3 instances or higher runningRedis version 6.x. For more information, seeRedis version 6.x.

³For more information about region-specific considerations, seeGeography and regions.