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Suggested answer

MRP runs for very long time

Posted on by 45

Hi All,

Our MRP started to take longer times every month and now it runs for almost 14 hours. This is a huge impact for us.

We have tried increasing helpers, upgrading SQL hardware from an infrastructure point of view.

From AX, When we see session logs, we find that the step-> Recalculate item levels takes most of the time (13+ hours).

We do not have customizations in these classes, but we do have a lot of items. Also, we have experienced behavior that it runs quite quicker( 2 hours) in weekends and on holidays where there are no active users.

Any pointers would mean a lot.

Thank you.

  • rpm Profile Picture
    rpm 10 on at
    RE: MRP runs for very long time

    Additional information for those interested...

    AX Environment: AX 2012R3 CU13

    The current MRP configuration related information:

    1. Single AOS Batch server dedicated to MRP batch

    • 4 CPU(s)
    • 32 GB Memory
    • 8 Maximum Batch Threads

    2. MRP Batch Job

    • 7 Helpers
    • Regenerative
    • Tracking process task duration

    3. Master Planning Configuration

    • BOM Circularity 
      • Level of circularity: Line
      • Check Strategy:  Optimize for low complexity
      • Max levels: 15
    • Number of tasks per bundle:  10
    • Use of cache: Maximum
    • Pre-processing/Post-Processing selected

    We have tried multiple changes to these settings without any success.

  • rpm Profile Picture
    rpm 10 on at
    RE: MRP runs for very long time


    I work with Vaishnavi.

    We actually don't receive any "item level is incorrect for item" in the mrp infologs. The only messages that appear is a line per helper indicating that coverage was updated:


    I have read the recommendation  "delete the previous plan" before running MRP from many blogs. However, I have not found a lot of information on what this does exactly.

    Also, which plan(s) should be deleted?  

    We are currently running two plans. A static master plan and a dynamic master plan. A nightly regenerative plan is being run on the static master plan, with the results being copied into the dynamic plan.

  • Suggested answer
    guk1964 Profile Picture
    guk1964 10,877 on at
    RE: MRP runs for very long time

    Check the mro log - you probably have al lot of these messages ;Item level is incorrect for item" xxx

    You should run mrp full regen when no-one else is logged on. 

    Under Periodic and BOM you have a routine called "Recalculate BOM Levels" -run this first, or at least once a week or whenever creating an ew item.

    To understand why read : and also why its not so easy tog et right.

    Consider whether al items need mrp planning, (and level update).

    Before you run mrp always delete the previous plan.

  • Suggested answer
    André Arnaud de Calavon Profile Picture
    André Arnaud de Cal... 288,420 Super User on at
    RE: MRP runs for very long time

    Hi Vaishnavi,

    You can watch a YouTube movie about this topic. Several years back, Microsoft had a session on an event which got recorded: Help! MRP is slow! It can be an eye-opener for you as there are many tips to improve the performance..

  • Suggested answer
    RE: MRP runs for very long time

    Hi Vaishnavi,

    The fact that “Recalculate item level” is taking the most time, can be related to the BOM circularity check. Please check how the Circularity check strategy is setup, see following blog for details:

    There is a number of KB’s related to the performance of this functionality, (recalculating the BOM level) that I suggest you to check: KB: 4042154 Poor performance of recalculating the BOM level with high number of variant items; KB: 4020816 Circularity check is very slow on the BOM; KB: 4022020 AX takes a long time to finish the Check circularity process for large amount of data; KB: 3192966 Improve BOM level calculation performance, causing delays in MRP and firming; KB: 4093436 SHA1HASH impacting slow performance of MRP BOM level recalculation and circularity check; KB: 4076859 High memory usage during BOM circularity check with high complexity option leads AOS to crash.

    Thank you,

    Adrian Serban

  • Vaishnavi Profile Picture
    Vaishnavi 45 on at
    RE: MRP runs for very long time

    Thanks Sergei,

    We have scheduled the MRP at night times currently so that user activity is less. Its same time window during weekdays and weekends.

  • Suggested answer
    Sergei Minozhenko Profile Picture
    Sergei Minozhenko 23,083 on at
    RE: MRP runs for very long time

    Hi Vaishnavi,

    Are you running the same job on workdays and on weekends with the same parameters? Is there any time window on workdays when user activity is minimal and you can run MRP at this time?

    Personally I would start with real-time query analysis (, DB maintenance, and index tuning (check missing index

    Additional information can be found in

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