"Is there an advantage in using a backing store to save on memory?"
- I assume you're referring to how the caching application block works where it still uses an in memory cache even when using a persistent backing store, am I correct? If yes, then the advantage will be the fact that when you're retrieving an object
from the cache, especially when using a database backing store, the code will no longer need to go to the database itself but rather rely on the in memory cache. This saves you from creating a database call.
And yes, the cache manager will still keep the number of items configured for the cache.
"Can there be kind of batch of items in memory with the rest of the backing store?"
- Currently, this isn't supported. You would have to create a custom implementation of a backing store.
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