Features and Limitations

This page provides details about vector search features and limitations.


Vector search is available on standalone versions from 7.2 across all tiers and all the supported regions.

Index Restrictions

The following outlines the limitations of the index:

  • The maximum number of attributes in an index cannot exceed 10.
  • A vector's dimension cannot exceed 32,768.
  • The M value for HNSW must not go beyond 2M.
  • The EF Construct value for HNSW must not exceed 4096.
  • The EF Runtime value for HNSW must also not surpass 4096.


Vector search facilitates vertical scaling through the integration of thread pools dedicated to executing vector search operations.

Memory Consumption

Vectors are duplicated, being stored both within the Redis keyspace and the vector search algorithm.


Owing to the asynchronous nature of executing tasks by thread pools, vector search operations don't adhere to transactional semantics.

RDB Snapshots

  • Vector search RDB snapshots are incompatible with non-vector search Redis instances due to specialized index formatting.
  • Importing vector search RDB snapshots from other vector search solutions other than Memorystore for Redis is not supported.