Is there any way we can determine estimate time that it would take to perform the segmentation process in our environment?
Release : 20.2
Component : CA Performance Center
Unfortunately, this is environment specific, and the method of estimation is post-expansion:
Note that there is no requirement to segment the tables right after the expansion.
The segmentation can reduce disk space and does seem to help with query performance.
You can do the expansion, then segment at a later time, and it does not need to` be done all at once.
You can segment while the DA is running (note the performance note in the guide).
You could do the option to create a script and then run each command in the produced script during off-hours until complete across multiple days.
So the segmentation can be done at a later time, over time, as needed.