Data Eviction Policies
For each database, you can choose from these six supported data eviction policies:
|allkeys-lru||Evicts the least recently used (LRU) keys out of all keys in the database|
|allkeys-random||Randomly evicts keys out of all keys in the database|
|volatile-lru (default)||Evicts the least recently used (LRU) keys out of keys with an "expire" field set|
|volatile-random||Randomly evicts keys with an "expire" field set|
|volatile-ttl||Evicts the shortest time-to-live and least recently used keys out of keys with an "expire" field set|
|no eviction||Returns error if memory limit has been reached when trying to insert more data|
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).
Note: Active-Active Geo-Distributed CRDBs will always operate in noeviction mode.