Change Data Capture and Always On

As I was going through some MS documentation, I happened to see the below excerpt. Could you please shed some lights on the same ?

We are seeing some overhead on CDC on our load test, hopefully, it may help us understand better of the below. Thanks in advance!

Question: What do we mean by "changing enumeration" here? Is there any setting or its just represent the secondary usage?

Change Data Capture and Always On

When you use Always On,change enumeration should be done on the Secondary replication to reduce the disk load on the primary.

Ref: https://docs.microsoft.com/en-us/sql/relational-databases/track-changes/change-data-capture-and-other-sql-server-features?view=sql-server-2017

Please mark this reply as answer if it solved your issue or vote as helpful if it helped.
 [Blog]  [LinkedIn]