Loading large mnt files into Xcenter

Xadmin 20.0.1.0.40

Our client is moving from ORPOS to Xstore. They are an established retailer (over 800 stores) with the number of items ranged to each store varying between 1 million and 25 million.

(That's 25 million distinct sellable items, not 25 million stock on hand )

We are currently converting the RMS mom jar file into the corresponding Xstore mnt files.

Creating the mnt is not an issue, but loading such large mnt files into Xoffice takes a long time.

Has anyone had experience porting a customer with so many items? Do you have any useful tips to share?

Thanks

Paul