docs: Add message that Cube Store will replace Redis (#5011)

Author: keydunov

docs/content/Caching/Overview.mdx

@@ -6,8 +6,11 @@ menuOrder: 1
 ---
 
 Cube.js provides a two-level caching system. The first level is **in-memory**
-cache and is active by default. We recommend using [Redis][link-redis] for
-in-memory cache when [running Cube.js in production][ref-production-checklist].
+cache and is active by default. Currently, [Redis][link-redis] is being used for
+in-memory cache and queue management for [clsutered Cube
+deployments][ref-production-checklist]. Cube Store will [replace
+Redis][replace-redis] in late
+2022.
 
 Cube.js [in-memory cache](#in-memory-cache) acts as a buffer for your database
 when there's a burst of requests hitting the same data from multiple concurrent
@@ -85,9 +88,7 @@ database to populate the cache with the results and return them.
 ### <--{"id" : "In-memory Cache"}--> Refresh Keys
 
 Cube.js takes great care to prevent unnecessary queries from hitting your
-database. The first stage caching system caches query results in Redis (or in
-the in-memory store in development), but Cube.js needs a way to know if the data
-powering that query result has changed. If the underlying data isn't any
+database. The first stage caching system caches query results, but Cube.js needs a way to know if the data powering that query result has changed. If the underlying data isn't any
 different, the cached result is valid and can be returned skipping an expensive
 query, but if there is a difference, the query needs to be re-run and its result
 cached.
@@ -193,3 +194,4 @@ versions.
   /deployment/production-checklist#set-up-refresh-worker
 [ref-schema-ref-cube-refresh-key]: /schema/reference/cube#refresh-key
 [ref-schema-ref-preaggs]: /schema/reference/pre-aggregations
+[replace-redis]: https://cube.dev/blog/replacing-redis-with-cube-store

docs/content/Caching/Running-in-Production.mdx

@@ -13,6 +13,14 @@ Cube.js makes use of two different kinds of cache:
 In development, Cube.js uses in-memory storage on the server. In production, we
 **strongly** recommend running Redis as a separate service.
 
+<WarningBox>
+
+Cube Store [will replace
+Redis][replace-redis] for in-memory cache and queue management in late
+2022.
+
+</WarningBox>
+
 Cube Store is enabled by default when running Cube.js in development mode. In
 production, Cube Store **must** run as a separate process. The easiest way to do
 this is to use the official Docker images for Cube.js and Cube Store.
@@ -248,3 +256,4 @@ allows requests from the Cube.js deployment.
 [ref-caching-partitioning]: /caching/using-pre-aggregations#partitioning
 [ref-config-env]: /reference/environment-variables#cube-store
 [ref-config-env-cloud-storage]: /reference/environment-variables#cloud-storage
+[replace-redis]: https://cube.dev/blog/replacing-redis-with-cube-store

docs/content/Deployment/Overview.mdx

@@ -34,7 +34,11 @@ one or multiple API instances, a Refresh Worker, Redis and a Cube Store cluster.
 pre-aggregated data or connected database(s) for raw data. The **Refresh
 Worker** builds and refreshes pre-aggregations in the background. **Cube Store**
 ingests pre-aggregations built by Refresh Worker and responds to queries from
-API instances. **Redis** is used to manage the queue and query-level cache.
+API instances.
+
+ **Redis** is used to manage the queue and query-level cache. Please note, we
+are planning to [replace Redis with Cube Store][replace-redis] for in-memory cache and queue management in late
+2022.
 
 API instances and Refresh Worker can be configured via [environment
 variables][ref-config-env] or [cube.js configuration file][ref-config-js]. They
@@ -283,6 +287,14 @@ services:
 
 ## Redis
 
+<WarningBox>
+
+Cube Store [will replace
+Redis][replace-redis] for in-memory cache and queue management in late
+2022.
+
+</WarningBox>
+
 Cube.js uses Redis, an in-memory data structure store, for query caching and
 queue.
 
@@ -327,7 +339,7 @@ If you want to run Cube.js in production without Redis, you can use
 
 <WarningBox>
 
-Serverless and clustered deployments can't be run without Redis as it is used to
+Clustered deployments can't be run without Redis as it is used to
 manage the query queue.
 
 </WarningBox>
@@ -342,3 +354,4 @@ manage the query queue.
 [ref-deploy-sls-gcp]: /deployment/platforms/serverless/google-cloud
 [ref-config-env]: /reference/environment-variables
 [ref-config-js]: /config
+[replace-redis]: https://cube.dev/blog/replacing-redis-with-cube-store

docs/content/Deployment/Production-Checklist.mdx

@@ -70,6 +70,14 @@ configured database][ref-config-connect-db] to set it up.
 
 ## Set up Redis
 
+<WarningBox>
+
+Cube Store [will replace
+Redis][replace-redis] for in-memory cache and queue management in late
+2022.
+
+</WarningBox>
+
 Cube.js requires [Redis](https://redis.io/), an in-memory data structure store,
 to run in production.
 
@@ -168,3 +176,4 @@ deployment's health and be alerted to any issues.
 [ref-config-env-vars-general]: /reference/environment-variables#general
 [ref-api-readyz]: /rest-api#readyz
 [ref-api-livez]: /rest-api#livez
+[replace-redis]: https://cube.dev/blog/replacing-redis-with-cube-store