Database Eviction Policies - Redis Enterprise Software | Redis Labs https://redislabs.com/redis-enterprise-documentation/administering/database-operations/eviction-policy/
Eviction policies
The eviction policy designates a data eviction method for Redis Enterprise Software (RS) to use when the database size reaches its limit. You can select any of the following:
| Policy | Description |
| noeviction | Returns an error if the memory limit has been reached when trying to insert more data |
| allkeys-lru | Evicts the least recently used keys out of all keys |
| allkeys-random | Randomly evicts keys out of all keys |
| volatile-lru | Evicts the least recently used keys out of all keys with an “expire” field set |
| volatile-ttl | Evicts the shortest time-to-live and least recently used keys out of all keys with an “expire” field set. |
| volatile-random | Randomly evicts keys with an “expire” field set |
One mechanism to avoid this, but still keep performance is to use Redis on Flash. It can span your database across RAM + Flash Memory and intelligently manage what data is hot and should be in RAM and what data is not and can be on Flash memory (SSD).
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