Redis Eviction Policies
An eviction policy is a rule by which Redis evicts keys to free up memory when memory consumption reaches the set limit. Read more about eviction policies in the Key eviction documentation in the Redis docs.
You can view the list of eviction policies.
You can select an eviction policy when creating a cluster or change it in an existing cluster.
Memory limit for key storage
The memory limit for storing keys is set in the maxmemory parameter. The default maxmemory value is 75% of the RAM on a cluster node. The remaining 25% is mandatory reserved for Redis system mechanisms.
You can change the maxmemory value only in Redis version 8:
- when creating a cluster;
- or when changing the eviction policy in an existing cluster.
You can change the value in the range from 1% to 75%. If you specify a value less than 75%, the remaining memory can be used by Redis system mechanisms.
List of eviction policies
Change the Eviction policy
We recommend changing the policy only if you are sure about the consequences — there is a possibility of partial data loss.
Redis 6
Redis 8
- In the Dashboard, on the top menu, click Products and select Managed Databases.
- In the Databases section, open the Active tab.
- Open the cluster page → Settings tab.
- In the Eviction Policy block, click Change.
- In the Maxmemory Policy field, select an eviction policy.
- Click Save.