The problem you have described is quite vague. You may need to do more analysis to discover the proble,.Some questions
1-Is the R3190 repost running on a scheduler? Are there other scheduled jobs running or in same queue?
2-When the R3190 runs for 4-5 hrs, has there been a significant change in work orders, e.g, MRP creating new work orders or sales orders driving new ones? Don't forget the R3190 is checking F4801, F3111,F41021 to update/clear commitments.
3-Check your processing options and data selection of R3190. You may need to narrow these down