Memory management for Azure Managed Redis (preview)
Eviction policy
Choose an eviction policythat works for your application. The default policy for Azure Managed Redis (preview) is volatile-lru, which means that only keys that have a TTL value set with a command like EXPIRE are eligible for eviction. If no keys have a TTL value, then the system won't evict any keys. If you want the system to allow any key to be evicted if under memory pressure, then you may want to consider the allkeys-lru policy.
Keys expiration
Set an expiration value on your keys. An expiration removes keys proactively instead of waiting until there's memory pressure. When eviction happens because of memory pressure, it can cause more load on your server. For more information, see the documentation for the EXPIRE and EXPIREAT commands.
Monitor memory usage
Consider adding alerting on "Used Memory Percentage" metric to ensure that you don't run out of memory and have the chance to scale your cache before seeing issues. If your "Used Memory Percentage" is consistently over 75%, consider increasing your memory by scaling to a higher tier. See here for information on tiers.