A Redis eviction policy under which writes are refused, rather than keys removed, once memory is exhausted. Azure Managed Redis needs it, together with the Enterprise clustering policy, for RediSearch.
Read more: Microsoft Learn
In the Ultra Transcenders books
Each book explains NoEviction in context, with comparison tables and the common traps.
Terms in this definition
- Eviction policy
The Redis setting that decides which keys get dropped once memory runs out. Azure Managed Redis uses volatile-lru by default, which removes only keys carrying a TTL, while RediSearch needs NoEviction.
- Azure Managed Redis
Successor to Azure Cache for Redis: a managed, Redis Enterprise-based in-memory store, with Memory Optimized, Balanced, Compute Optimized and Flash Optimized tiers.
- Enterprise
Any group of organisations with shared goals. Examples range from an entire company or one of its divisions to a government department, or several organisations working as partners or along a supply chain.
- Clustering policy
A choice made when creating Azure Managed Redis (OSS, Enterprise or Non-clustered) that controls how clients see its shards. RediSearch needs Enterprise, and an OSS or Enterprise choice is permanent.
- RediSearch
A Redis module for Azure Managed Redis that provides secondary indexes plus full-text and vector search. It can only be turned on when the cache is created and needs Enterprise clustering with the NoEviction policy.