Functional Setup Manager - Import / Export for HCM Modules Performance issues

Summary

Exporting " Compensation Management " , " Workforce Deployment ", " Workforce Development " at the Offering level from one instance to another having serious performance issues.

Content

I am Exporting " Compensation Management " , " Workforce Deployment ", " Workforce Development " at the Offering level from Source (19A) instance to Target (19B) instance and the import has been running for more than 36+ hours and it is Progressing on " Position Valid Grade " for more than 12+ hours and as per the count of processed records in the log file, it is not moving efficiently. So general question 

1) Is there any known performance issues with Functional Setup Manager with HCM Offerings ? 

2) Do these processes run as LOW PRIORITY and could that be a reason for this performance ?