# MRP Running Extremely Slow **URL:** \ **Category:** Epicor ERP 10\ **Tags:** e10\ **Created:** [July 14, 2020, 2:33am UTC](https://www.epiusers.help/t/mrp-running-extremely-slow/68921 "2020-07-14T02:33:02Z")\ **Posts on this page:** 1\ **Showing post:** 16
**Author:** ![JasonMcD](https://www.epiusers.help/user_avatar/www.epiusers.help/jasonmcd/32/22326_2.png) [@JasonMcD](https://www.epiusers.help/u/JasonMcD)\ **Post date:** [April 26, 2022, 1:00pm UTC](https://www.epiusers.help/t/mrp-running-extremely-slow/68921/16 "2022-04-26T13:00:35Z")
I’ll say this. I will never, ever add UD fields to JobMtl. It is off limits in my world. I tried once. It went very badly for MRP. Have you looked at the logs? You might find that one process gets hung up on a really popular part number: > [@Rant - MRP bottlenecking (Waiting for next part)](https://www.epiusers.help/t/rant-mrp-bottlenecking-waiting-for-next-part/83041): > > MRP takes forever. I know, earthshattering news. What I found today is that I have a kind of unsolvable problem. Basically, our sales backlog is so lopsided to two part numbers that using multiple process in MRP has a really finite limit of getting any more efficient. Here’s the situation. Roughly 100% of the revenue in the main plant comes from engineer-to-order, make-to-order trucks. An order might have dozens of lines for the same exact truck, but they are all quantity of 1 and make direct… --- _[View the full topic](https://www.epiusers.help/t/mrp-running-extremely-slow/68921)._