MRP performance concerns with large numbers of materials

[Former Member]

I am in the design and build phase for a new SAP implementation. We

will be using time-phased planning with requirements as the MRP type

for all materials, and MRP will run once a week on a sunday night. Each

MRP run will probably involve planning about 50,000 different materials

in each of two plants (total 100,000 plant/materials), and this volume

may well double to 200 000 plant/materials over the next 2-3 years.

We are concerned about the runtime and system resources required for

such a large MRP run. We wont have the production box set up for some time, and we wont be in a position to run any volume testing until shortly before go-live next year - we certainly dont want any nasty surprises then!

I know this is not an exact science, but I would like to know if anyone out there has experience of running MRP and planning a similar (or larger) number of materials. I dont think it matters much if you use a different MRP type, but please bear in mind that net change planning can dramatically reduce the number of materials planned, and I am interested in the number of materials which are actually planned during each MRP run, rather than the number which could potentially be planned.

If you do have such experience, could you share a little information about your system resources, number of materials, and the eventual runtimes you achieved in MRP? This may help me to predict whether we will have a problem at go-live, and to make sure our technical people allow adequate resources when they build our production system

Thanks, Chris

[Former Member · Accepted solution]

Hi,

We had similar situation in one of the implementation projects. We has some discussion on the performance of MRP run over a perod of time. The solution we had was to utilize the parallel processing options of MRP run. We had five application servers for the production system. We had two options either dedicate one server for exclusive MRP run or distribute the MRP processes across the different servers. Initially we were succesful in running MRP in one server after go-live. Later as the database grew and no of materials increased exponentially, the plan had to be changes & the MRP processes we run across different servers apart from one exclusive MRP server.

So one solution may work for some time and after some time when database would grow you would have to look for other alternatives like increasing the server capacity, adding additional server and so on. Other basis tools wouls also be required to reduce the time for MRP run.

For eample one of the plant use to take around 2 hrs just after go-live, this increased to 10 hrs in si months time. So we created MRP jobs for each plant separately and run them parallal. Then we had to run MRP jobs for other plants which were supplying to this plant.

May be you can choose a solution whcih should for for atleast 6 month post go-live. During this time, monitor the MRP jobs and decide if you need to change your plans.

Regards

Vineet

[Former Member · Accepted solution]

Hi Vineet

Could you give me any rough figures for your MRP run? What I really would like to know is how many materials were actually planned in one of your large MRP runs, and roughly how long MRP took to plan that number of materials. Of course our hardware and data will be different, but if I can get some rough figures, I can at least make an initial estimate of how long our MRP runs could take. If you can give me any details about your hardware sizing, this would also be useful, but the most useful information for me is just to get some idea of number of materials planned vs. MRP runtime

Thanks for your input, it is much appreciated, Chris

[Caetano · Accepted solution]

Hello

Take a look on the reports provided on the following note to get this information:

https://service.sap.com/sap/support/notes/1865330

BR

Caetano

[Former Member]

Hi Chris,

Am running MRP for 40 plants simultaneously and the total materials in the plants are 95000. When a MRP is run using the netchange key the the materials planned are approximately 30,000. Am doing a parallel processing with 2 sessions and takes rougly 20 minutes to take this run.

Hope this helps.

Tarang