Merge pull request #2517 from redis/DOC-6026-rdi-when-to-use

DOC-6026 implemented feedback in RDI "when to use" page

Author: andy-stark-redis

content/embeds/rdi-when-to-use-dec-tree.md

@@ -114,7 +114,8 @@ questions:
         text: |
             Is your total data size smaller than 100GB?
         whyAsk: |
-            RDI has practical limits on the total data size it can manage. Very large datasets may exceed these limits.
+            RDI has practical limits on the total data size it can manage, based
+            on the throughput requirements for full sync.
         answers:
             no:
                 value: "No"

content/embeds/rdi-when-to-use.md

@@ -2,19 +2,20 @@
 
 RDI is a good fit when:
 
-- You want to use Redis as the target database for caching data.
+- You want your app/micro-services to read from Redis to scale reads at speed.
 - You want to transfer data to Redis from a *single* source database.
 - You must use a slow database as the system of record for the app.
 - The app must always *write* its data to the slow database.
 - Your app can tolerate *eventual* consistency of data in the Redis cache.
 - You want a self-managed solution or AWS based solution.
 - The source data changes frequently in small increments.
 - There are no more than 10K changes per second in the source database.
-- The total data size is not larger than 100GB.
 - RDI throughput during
-  [full sync]({{< relref "/integrate/redis-data-integration/data-pipelines#pipeline-lifecycle" >}}) would not exceed 30K records per second and during
+  [full sync]({{< relref "/integrate/redis-data-integration/data-pipelines#pipeline-lifecycle" >}}) would not exceed 30K records per second (for an average 1KB record size) and during
   [CDC]({{< relref "/integrate/redis-data-integration/data-pipelines#pipeline-lifecycle" >}})
-  would not exceed 10K records per second.
+  would not exceed 10K records per second (for an average 1KB record size).
+- The total data size is not larger than 100GB (since this would typically exceed the throughput 
+  limits just mentioned for full sync).
 - You don’t need to perform join operations on the data from several tables
   into a [nested Redis JSON object]({{< relref "/integrate/redis-data-integration/data-pipelines/data-denormalization#joining-one-to-many-relationships" >}}).
 - RDI supports the [data transformations]({{< relref "/integrate/redis-data-integration/data-pipelines/transform-examples" >}}) you need for your app.
@@ -31,7 +32,8 @@ RDI is not a good fit when:
   than *eventual* consistency.
 - You need *transactional* consistency between the source and target databases.
 - The data is ingested from two replicas of Active-Active at the same time.
-- The app must *write* data to the Redis cache, which then updates the source database.
+- The app must *write* data to the Redis cache, which then updates the source database
+  (write-behind/write-through patterns).
 - Your data set will only ever be small.
 - Your data is updated by some batch or ETL process with long and large transactions - RDI will fail
   processing these changes.