Maxmemory-policy allkeys-lru instead of volatile-lru?

I have a problem with Redis and Pimcore 5. From time to time the Redis cache runs out of memory.

In the Pimcore documentation I found this:

IMPORTANT! Other policies will cause random inconsistencies of your data!

maxmemory-policy volatile-lru

Most of the Redis entries (Pimcore assets, documents, …) do not have an expiration time set.
ttl returns -1, which means according to the Redis documentation

The command returns -1 if the key exists but has no associated expire.

With the volatile-lru policy, a key with an expire set will be removed using an LRU algorithm.

I think this is the reason why the memory will be full at some point and does not accept any additional entries. All entries without expire will not be deleted with this policy.

Is it really not possible to use the policy allkeys-lru? I guess this would free up memory even if there is no expire set.

Thank you for your help!