release memory for Redo as soon as possible

Customer has many end users (around 100) and all of them are connecting to a shared server(1.5TB memory available) via RDP and using Analyst to analyze huge amount of data (up to hundreds of GB). Sometimes memory usage of Analyst application is very high (up to 1TB) despite actual data size is not that big.

According to TIBCO support,

Memory for Redo is not released until the analysis is closed. It's not possible to force-release it. 

It's indeed possible that end users may add data operations and undo it frequently so the customer is requesting that memory for Redo should be released ASAP.

Here is my test results of memory usage

(1) load tableA (size is 1.5GB): 2000MB

(2) load tableB (size is 1.5GB): 3500MB

(3) add rows from B to A: 5000MB

(4) undo: still 5000MB

(5) add new page ( in order to clear the redo generated by (4)): still 5000MB

(6) add rows from B to A once again: still 5000MB , this means memory was kept for redo (4)

(7) undo again: still 5000MB

(8) add rows from A to B: 6500MB , this means meory kept for redo (7) was not reused and not released

We wish,

(a) memory for Redo of step (4) should be released after step (5) because redo of step (4) is not possible any more(already overwritten by step (5) ).

(b) memory for Redo of step (7) should be reused by step (8) because redo of step (7) is not possible any more(already overwritten by step (8) ).