The client gets an exception similar to:
ReplyError: ERR max request size exceeded
Your command exceeds the max request size which is 1Mb for "Free" and "Pay as you go" databases.
You can split your data into smaller chunks and send them in seperate commands.
You can upgrade your database to Enterprise as it has higher limits. Also you can submit quota increase request in the console or you can contact firstname.lastname@example.org about the options with higher max request size limit.
max-request-size-limit is about the size of a single request. Your data structure (like list, set) can exceed the max request size limit without any problem. If you try to load all elements in the list with a single request then it can throw the max-request-size-limit exception.