In Redis, you can control cache expiration and elimination behavior by configuring cache invalidation policies. Here are some configuration options related to cache invalidation:
Expiration time (expire): Use the EXPIRE command to set the expiration time for a specific key, in seconds. For example, set key "mykey" to expire in 3600 seconds:
EXPIRE mykey 3600
In the Redis configuration file, you can also use the expire configuration item to set the default expiration time of all keys in seconds:
# redis.conf expire 3600
Eviction policy: When memory is insufficient, Redis can delete expired or infrequently used keys according to different eviction policies. Redis supports the following elimination strategies:
Volatile-lru: Use the Least Recently Used (LRU) algorithm to eliminate keys with an expiration time.
Volatile-ttl: Eliminate keys based on expiration time. The earlier they expire, the earlier they will be eliminated.
Volatile-random: Randomly eliminate keys with an expiration time set.
allkeys-lru: Use the LRU algorithm to eliminate all keys, regardless of whether the expiration time is set.
allkeys-random: Randomly eliminate all keys.
Noeviction: No key will be eliminated. When there is insufficient memory, new write operations will return an error.
In the Redis configuration file, you can use the maxmemory-policy configuration item to set the elimination policy, for example:
# redis.conf maxmemory-policy volatile-lru
Memory limit: Use the maxmemory configuration item to set the maximum memory used by the Redis instance. When this limit is reached, the key is deleted according to the elimination strategy. For example:
# redis.conf maxmemory 1GB
Please note that the specific settings of the above configuration options need to be adjusted according to your application scenarios and needs. It is recommended to test and monitor based on actual conditions to ensure that the selected strategies and settings perform well in the production environment.