MS project - multiple project resource problems

Member for

24 years 8 months

Niek,

I tried the feature you described. It is a large step forward though due to the poor leveling algorithms the results are not reliable.

In the sample project I created the resource constrained float for the project as a whole is 5 days and only two activities are resource critical that is obviously wrong. The project schedule was uploaded at http://www.ephotohut.net/viewpic.cfm?pic=280805100948.jpg

In the text field next to activity names you will find assigned resource abbreviations.

In any case it is a great improvement.

What do you think about the sample project?

Regards,

Vladimir

Member for

20 years 7 months

Vladimir,



You have to deselect the leveling option "Preserve scheduled early and late dates", otherwise it will keep the critical path of the original unleveled schedule.



I’m curious to hear your findings.



Cheers,



Niek.

Member for

24 years 8 months

Hi Niek,

I did not see this feature in Primavera software. I will try to have a look. I have an access to P3ec and hope that there is something like this too that I did not notice. Please advise me where to find.

Spider Project calculates Resource Critical Path and resource constrained floats since 1992. So when Goldratt suggested Critical Chain in 1997 I had thought that at last some guy in the West understood that resources are of essence. I talked about Resource Critical Path in my presentations at PMI conferences in 1994 and 1996, but had no feedback.

Thank you for an interesting information.

Vladimir

Member for

20 years 7 months

Hi Vladimir,



This discussion probably belongs somewhere else, so with the risk that we get thrown out of this forum category:



I learned about the subject as "resource critical activities" from Fromdahl way before Goldratt started to claim the credit for it.



I don’t know which Primavera product you are referring to but I’m talking about Project Management 4.1 which is part of the IT Project Office (a.k.a. TeamPlay) suite. It shows a critical path that marks resource critical activities, which makes a lot more sense than relying on a precedence float concept that doesn’t hold in resource constrained schedules.



Cheers,



Niek.

Member for

24 years 8 months

Niek,

I agree that Primavera suggests more options and one of them that is most valuable is the ability to add custom leveling criteria and priorities. Unfortunately these simple criteria rarely lead to optimal solutions though an initial schedule may be improved. I don’t understand why Primavera and MS Project developers don’t even try to optimize project resource-constrained schedules. There are unused reserves that can save a lot of time and money. One of Spider Project advantages that I consider as the most attractive is its ability to optimize resource-constrained schedules. But it is attractive to those who understands the problem. I suspect (as you do) that most schedulers just believe that the software provides an optimal solution without trying to analyze scheduling results.

I don’t understand what do you mean by "a critical path that is also making sense after leveling".

A set of activities with the zero time reserves constitute resource-critical path (you know it as Critical Chain). Do you mean this or something else? I did not noticed that Primavera started to calculate resource critical path. And Total Float (Slack) fields in both products show wrong reserves if resources are limited.

Member for

20 years 7 months

Yes Vladimir, you are absolutely right.



When I said resource leveling is complex I was certainly referring to the fact that the mainstream scheduling software rarely provides the optimal schedule after leveling.



There are however significant differences between MSP and Primavera Project Management in this respect:

- A leveling log that shows what is directly an indirectly delayed

- The ability to level selective resources

- The ability to add custom leveling criteria and priorities

- The ability to avoid path conversion

- Independent resource leveling (5.1)



And last but not least, a critical path that is also making sense after leveling.



I bet Spider software has a few extras but it is not entirely correct to state that MSP and Primavera are providing the same functionality in this area.



Hope this helps more people to understand that this subject is more than just pushing buttons.



Cheers,



Niek.

Member for

24 years 8 months

And you will be happy (with MS Project or Primavera – does not matter much) until one day you will discover that the resource constrained schedules advised by the package can be dramatically improved.

It is interesting that nobody discusses the quality of resource constrained schedules produced by PM software.

Member for

20 years 7 months

JG,



The MS Project leveling capabilities are very limited and you should certainly not expect any miracles from it.



Furthermore leveling itself is quite complex so you really need to understand what you are doing certainly if want to level resources across multiple projects.



When MSP hits an overallocation it cannot resolve it starts to complain (unless you switch scheduling messages off) and then you’ll need to find out where that problem comes from.



Here a just a few tips:

- Constraints in the schedule are a big killer for leveling

- If you constrain MSP to schedule "only within the available slack" it can’t extend the end date so it has less room to find a solution.

- Make sure your schedules are simple and start going to the schedules in step-wise approach. Add two schedules to the master and see how this works.

- Start with one simple schedule until you have reached acceptable results and don’t try to level all 20 concurrent schedules in one go.



Hope this helps,



Niek.



P.S. If the above does not help, buy yourself Primavera Project Management 5.0, open all the 20 schedules in one go and level them like it is a single project.