How long are cached results persisted by default?

Hi there!

I have been reading through the prefect docs on caching, and ran into some ambiguous language I wanted to clarify:

You may optionally provide a cache_expiration timedelta indicating when the cache expires. If you do not specify a cache_expiration , the cache key does not expire.

Q1: When it says that the cache key does not expire, does this imply that the cached results are stored and persisted forever?
Q2: If Q1 is true, then can you clarify whether the cached data will be stored on the persistent volume, in memory, or both?
Q3: Is there an external way to clear out all cached results after say ~30days, in the case where no expiration was declared in the @task decorator?


Reference Docs: Tasks - Prefect 2 - Coordinating the world’s dataflows