Hi Vladimir,
Look what I found in MSP. It use the longer duration of parallel activity as leveling priority. (see below) Very interesting.


Best Regards,
Rodel

Rodel,
activity ID does not play any role in Spider levelling.
We recommend our users to make their activity IDs meaning what is activity type, where it is, who is performing, etc - not numeric but text based. There is no such thing as proper order of activity IDs.

It would be strange if changing activity code will change the schedule. For manual prioritization we use Priority field.

So P6 default activity levelling priority is Activity ID. Thank you for the information. I did not know this.

Best Regards,
Vladimir

Yes, you are right, but these priorities still produce poor schedules. Even for the project that we scheduled none of them produce good result. But for my surprise if to run levelling several times using the same priority the schedule will change each time and even become optimal (for this particular example). But unstable schedule create different problems.

This approach - selecting the priority among activity fields we call Standard. But in Spider Project you can also select Optimization and may be sure that the schedule is close to optimum.

And manual levelling is exhausting exersize in any case - even when the schedule is properly created. And I don’t think that this is the way to find the best solution in the large schedules.

Best Regards,
Vladimir

Rafael,
I think that the ways of using Spider is proper to discuss in Spider Project forum.
We recommend to apply Spider risk management - this is the best way to manage projects.
Vladimir

Rodel,
applying manual priorities is the same as levelling projects manually. If the the number of activities is small it is possible, for large projects you will not know what priorities to change.
I don’t think that such what if estimates are practical in the real schedules.
Best Regards,
Vladimir

Hi Vladimir,
That’s what I did. I schedule the project first and change the leveling priority as shown on the figure that I posted (see 1st column). I change task "Technical Requirements" as 1-Top and the rest are 3-normal then level again. I also change back the leveling priority to 3-Normal for all and I goes back to the original result that I posted for comparison (Post #160 & #158)

Best Regards,
Rodel

Hi Rodel,
please inform us what levelling priority did you use.
And I suggest to repeat the levelling from the beginning - first schedule the project and then level. Are the results the same?

Best Regards,
Vladimir

I agree Rafael, that is why Preserve schedule early and late date should not be used when levelling resources. It is used only for analysis and comparing the movement of dates after the levelling. If proper levelling is done, the correct float will be given.

See belowcomparison:

Using Preserve schedule early and late date option:
Early and late date did not update and remain as original compare to start and finish date.


Proper levelling without using any option. Early and Late dates are updated as shown on Start & Finish dates.


Best Regards,
Rodel

Hi Rafael,
Thanks for the xer and correct me if I’m wrong. I downloaded the files that you shared and do the exercise. I suspect that the screenshot that you posted is level the resource using “Preserved scheduled early and late dates” options that its why it not showing the correct float. It forced primavera to retain early date which is the basis of calculating float. As shown below.

Note: I change the resource name to match on the screen shot that you used.

Here is the explanation using that option:
If you mark the Preserve Scheduled Early and Late Dates checkbox, the project’s current early dates are retained before levelling. In addition, when you preserve these dates, the module only forward-levels the schedule, which means that the early dates of activities from the start to the finish of the project are scheduled.
To review the levelled early dates, I show the Start and Finish dates to compare Early Start and Early Finish date as shown on the figure above.

If you clear the Preserve Scheduled Early and Late Dates checkbox, the module also performs backward levelling. Backward levelling schedules activities to occur as late as possible without delaying the project finish. The module reverses the levelling process, beginning at the project’s late finish and working towards the beginning of the project. If insufficient resources are available to schedule an activity on its late dates, the activity is advanced to an earlier date. When the schedule is levelled forward and backward (by clearing the checkbox to preserve scheduled early and late dates), the project’s early and late start/finish dates are updated as shown below.


On this exercise P6 clearly show that resource levelling facility is correct.

Best Regards,
Rodel

Hi Rafael,
I believed you shared wrong xer. It was the first exercise and not the same as what you posted.

Thanks,
Rodel

Rafael,
You can read PMRefMan if you need to understand your entire question as it will cover all the pages here in PP. Its self explanatory and I use default option when running resource leveling.

Ex: “Calendar for scheduling Relationship Lag ........................Predecessor Activity Calendar”
It is an option where most of Planning Software now is using to calculate relationship lag. The default on MS Project 98 to 2002 version, P3 and others planning software is Predecessor Activity Calendar. In P6 you can select as shown on my post link below.
.xer to .prx Post #6

Cannot leveled means not leveling that particuar activity (Forward, Backward) Please refer to the manual link below.
Primavera 6.1 Reference Manual

Best Regards,
Rodel

R. Catalan,
I’m cooled as the weather here in Melbourne is starting too breezed... and don’t mean for any fight.
I respect Rafael’s opinion but we stand P6 is correct.

Rafael,
Below is the report as requested.
Scheduling/Leveling Report - 15-Apr-10 12:09 AM - PM.exe
========================================================

Default Project..................................................Test

Projects:
Test............................................................Test For Resource Leveling

Scheduling/Leveling Settings:
-----------------------------
General
-------
Scheduling ......................................................Yes
Leveling ........................................................Yes
Ignore relationships to and from other projects .................Yes
Make open-ended activities critical .............................No
Use Expected Finish Dates .......................................Yes
Schedule automatically when a change affects dates ..............No
Level resources during scheduling ...............................No
Recalculate assignment costs after scheduling ...................No
When scheduling progressed activities use .......................Progress Override
Calculate start-to-start lag from ...............................Actual Start
Define critical activities as Total Float less than or equal to .0
Compute Total Float As ..........................................Start Float
Calendar for scheduling Relationship Lag ........................Predecessor Activity Calendar
Preserve scheduled early and late dates..........................No
Level resources only within activity Total Float.................No
Level Priority 1.................................................Activity Leveling Priority - Ascending
Level all resources..............................................Yes

Advanced
--------
Calculate multiple float paths...................................Yes
Calculate multiple float paths using.............................Total Float
Number of paths to calculate.....................................5

Statistics:
-----------
# Projects.......................................................1
# Activities.....................................................5
# Not Started....................................................5
# In Progress....................................................0
# Completed......................................................0
# Relationships..................................................3
# Activities with Constraint.....................................0

Errors:
-------
Warnings:
---------
Activities without predecessors..................................4
Project: Test Activity: A1000 1
Project: Test Activity: A1010 2
Project: Test Activity: A1020 3
Project: Test Activity: A1030 4

Activities without successors....................................2
Project: Test Activity: A1010 2
Project: Test Activity: A1040 5

Out-of-sequence activities.......................................0

Activities with Actual Dates > Data Date.........................0

Milestone Activities with invalid relationships..................0

Scheduling/Leveling Results:
----------------------------
# Projects Scheduled/Leveled.....................................1
# Activities Scheduled/Leveled...................................5
Data Date........................................................05-Apr-10 12:00 AM
Earliest Early Start Date........................................05-Apr-10 08:00 AM
Latest Early Finish Date.........................................17-Apr-10 05:00 PM
Number of float paths............................................0
Exceptions:
-----------
Critical Activities..............................................4
Project: Test Activity: A1000 1
Project: Test Activity: A1020 3
Project: Test Activity: A1030 4
Project: Test Activity: A1040 5

Activities with unsatisfied constraints..........................0

Activities with unsatisfied relationships........................0

Activities with external dates...................................0

Activities delayed due to predecessor delay......................1
Project: Test Activity: A1040 5

Activities delayed due to resource leveling......................2
Project: Test Activity: A1020 3
Project: Test Activity: A1030 4

Activities that cannot be leveled................................1
Project: Test Activity: A1010 2

Activities that cannot be leveled backward.......................1
Project: Test Activity: A1010 2

Activities that are not on any float paths.......................4
Project: Test Activity: A1010 2
Project: Test Activity: A1020 3
Project: Test Activity: A1030 4
Project: Test Activity: A1040 5

Rafael & Rodel,

Cool down guys, you’ve overtaken me in taking post #139.

Hey Rafael, have you subscribe to Mayweather vs Mosley fight this May 1? I’m very excited to see this fight. The same with Cotto vs Foreman.

Best regards,
R. Catalan

Rafael,

We just prove why and spider project don’t do it either because it over allocated which is the same as P6 clearly prompted on the log file.

We do the exercise fair and compare apple to apple as per your sample.

If you don’t want to open your eyes, it’s up to you and we respect it. As for the P6 users we still stand P6 have the same result and correctly leveled the resource.

Best Regards,
Rodel

Rafael,
We respect what you believed. We know that we cannot change what you insist and that your own opinion. We just proved based on your example that your claimed is wrong. It will not change until it’s proven. We love to know all the bugs we can encounter using P6 to be aware and not to compare. I am not defending P6 here. I just want to resolve the issue by doing the exercise as you requested for other to enlighten what is the result.
Best Regards,
Rodel

Rafael,
Sorry, I’m not sure what you want to portrait.
Again, if the planner/ user read the log file he will understand all information for error, warning, exclusion, out of sequence, not leveled, schedule override… etc…
As you said, it is the responsibility of the planner to correct all those findings. So what’s the problem there?

Best Regards,
Rodel

Rafael,

As I said, P6 is doing the same thing. Many options have been removed from P3 to P6 like extending or shorten duration when leveling. I’m not sure if the planner/user is aware of what P3 or P6 response to leveling when they are not reading the result log file. It’s all there what has been leveled, errors & warning, exclusion, number of activities leveled, number of activities wrong sequence or in correct logic etc… I believed most of the user just leveled and never read the report. I always check the report that is why I know what’s happening during the level, schedule, export, import etc...

I suggest all planner/ user to use/ read the log file to check what error or warnings indicated on the log file after executing application to understand what happened after the execution.

Best Regards,
Rodel

Rafael,

I believed P6 is the same not leveling over allocated resource. Maybe the only difference is Spider Project prompt the user that cannot level due to over allocated while P6 prompt the user by the way of log file.
As I mention earlier, I figure it out when I over allocated all resources and P6 did nothing. When I check the log file it mention not leveled for every activity having over allocated resource.

Vladimir,
I know what do you mean but this is not included on this exercise. We only comparing apple to apple as per example. Maybe we can demonstrate another problem illustrating this issue using same comparison again. I’m happy to know what bugs really reside on P6 so all users/planner become aware.

Rafael,
I used only same comparison with the sample that you illustrate. As I said (if you read my post) P6 did not touch or did not levelled Task 2 for having over allocated loading which is indicated on the log file. (A1010 not level using forward, A1010 not level using backward). On the figure comparison (apple to apple) using same resource loading it show exactly the same including resource histogram.

I suggest that if possible try overloading resource on Task 2 and let us know what will be the result. It’s very interesting to know if your tool will come up different result.

Best Regards,
Rodel

Rodel,
I will see this warning only looking to the specific resource histogram. In the projects with hundreds resources assigned it is impossible to check the histograms of all resources.
I still don’t understand why the float become larger for overallocated resource.
I would expect that the package will warn that the levelling is impossible without adding additional resources to resource pool because the quantity of resources assigned to the single activity exceeds available quantity. I think that it is logical.

Actually I don’t approve assigning hours without assigning quantities. In this case it is not possible to assign two resource units with 50% workload if the quantity is not specified.

Best Regards,
Vladimir

Dear Rodel,
please explain why
1) P6 does not warn about resource overload when resource is assigned 13h/day and calculated resource-constrained schedule?
2) the float is larger when resource requirements are higher?
I am intrigued by these results and want to play with P6 myself. I suspect that 13 hours/day may appear automatically if to shorten activity duration from 5 to 3 without reassigning resources, isn’t it? Very strange setting.

Spider Project would warn that you need additional units of resource R2 and will refuse to level the project.

Please explain.

Best Regards,
Vladimir

Hi Mimoune,

Actually, right now, I’m near your country.

Anyway, I supposed the intention is to do "resource levelling" so as to get the minimum duration possible.

This is considering that you will be using resource calendars as well as activities calendars which are not necessarily the same or consistent.

And I guess Vladimir is offering a solution, why not try it Mimoune?

Hi Rafael,

I believe that you cannot prove it with just your presentation below and you did not elaborate with the parameters that you had used (or used by someone else).

Best regards

pfffff sorry Anoon to hear that, anyway what are you doing in Philippine anyway !

Just to prove that i am really open mind, i think i was wrong, actually P6, give correct values for resource leveling including total float, but there is a hick.

in the case of a simple schedule ( 4 activities) P6, give a solutions which is so far from the optimum solutions, that automatically a normal joe will conclude it is wrong. but in reality( mathematical meaning) it is a correct solution in the sens that it satisfy the conditions( both links and resource availability)but unfortunately it increase project duration.

best regards
Mimoune

HI Anoon

i hope you are kidding me, there is no conspiracy here, i have no affiliation with Rafael, but i do have an advantage, which is i am a junior, it means, i don’t have any strong idea about any method, i am just learning, I don’t care really if P6 is better or not comparing to others packages. but i do care to have a correct results.

yes, as A P3 user, i set many rules for priority of resource leveling, it depends, total float, early start, etc, sometimes i just fellow the intuition of the construction manager, he wants to put more resources on a particular task, after all he is the responsible not me.

having saying that, and from a guy who is aware, there is no exact solutions for the problems of resource leveling, but rather many approach to solve the problem and give a good solution to satisfy both resource availability and logic constraints. all those rules are for getting better solution, let’s say optimizing the solutions. but no matter what you have set as rules the result must be correct.


i expect from the software to give me a correct solution, perhaps far from optimum, but nevertheless correct (it satisfy the conditions), otherwise it is an issue and should be declared by the vendor.

and for testing the four activities schedule, no need to check another package, manual calculation, can spot, that there is something not ok.

best regards
Mimoune

Hi Anoon,
please clarify what may be changed with the schedule and floats if to select task or resource dependent and all activities and resources have the same calendars.
I did not try to say anything about Spider but of course all restrictions shall be taken into account during scheduling (levelling) process. No one restriction governs - all shall be satisfied.
I did not understand if you tried Rafael example or not?
Resource levelling does not require tailoring - it shall create the project schedule based on the same data and satisfying all resource limitations. Besides the shortest resource constrained schedule means better resource utilization.

Best Regards,
Vladimir

hi all

that’s far what I got from experimenting in Primavera p6.
as far as you put only activities with one resources and without links, P6 handle well, and it give you the right Total float, but if you start with only four activities, and assigning two resources and some links, it level correctly the activities (max usage not reached) but you will get inaccurate total float, sometimes even some negative one.

notice here, i did not change any default rule

i hope i am wrong in my calculations, but it is a a very serious matter, we call this bug, or even worst, defective by design.

best regards

Mimoune

Hi Anoon,
please clarify what is not true?
Best Regards,
Vladimir

Thank you Vladimir for the links.

With kind regards,

Samer

Rodel,
I don’t mean you personally.
I wrote about general Client - Contractor relationships.
I think that the Client may require certain forms (formats) for the schedule submittals, what level of details shall the schedule include, but not what tools and methodologies to use for Contractor construction management.
Do you agree?

Best Regards,
Vladimir

Vladimir,

Thank you for your clarification. My apology if my wordings are not clear. We don’t dictates; we follow what is required and were agreed by the top management.

With Kinds Regards,
Rodel

Rodel,
maybe I did not understand you correctly.

You wrote:
“Clients or stakeholders always looking for systems that compatible to their system as much as possible so the data exchange and communications will much easier.” (If we use different systems from each other how are we able to communicate?)

From this I understood that you advocates the right of the Client to dictate to Contractors what project management tools shall be used.

I tried to explain that it may lead to worse project management and may create huge problems to Contractor’s management teams, that the Client and the Contractor have different requirements to the schedule model, etc. I think that the Client may require certain formats for the data that are submitted but has no rights to dictate what tools the Contractor shall use to manage its resources. At least it is not smart.

I am sorry if it was not clear, English is not my native language.

Best Regards,
Vladimir

I am sorry, Samer.
Most our clients speak Russian and the documents that are created are in Russian.
Besides most companies do not like to share their internal standards.
I will think what can be done and will write to you directly.
Best Regards,
Vladimir