Reliable dictionary vs Redis Cache

Question

I want to implement caching for Cosmos DB data. I read about Reliable Dictionary and Redis Cache.

I want to know:

(1) When to use Reliable Dictionary as a caching mechanism and what is the duration and capacity of cache?

(2) Redis cache is recommended but what is the capacity and duration of availability?

Answer 1

A reliable dictionary is a collection in c#, not a Service. The capacity depends on the memory of the service you host your application (eg App Service, Service Fabric, etc...). Also you have to manage the duration of the cach entries.

Redis Cache is Caching as a Service . The Capacity depends on the SKU and is up to 530GB. You have different ways to control the duration of an entry. You can use a absolute (datetime) or sliding expiration (eg a entry get removed when not accessed within the last 30 minutes).