Creating a non splitable task

Member for

18 years 11 months

That's a very good suggestion from Rafael to use a start milestone with a calendar exclusion - would work just as well in MSP as in Spider.  As long as the shutdown period will never shift, it is probably better than my suggestion.

Although you can't use formulas to set schedule constraints in MSP, you could accomplish the same thing using some vba (i.e. "macro" program) to mimic either approach.

Member for

21 years 8 months

Try using a milestone not allowed to work during shutdown plus some time before shutdown as needed as not to allow any portion of the activity to occur during the shutdown.  Please take a look at the following figures.

 photo NSSD01_zpsxerkkhgr.jpg

 photo NSSD02_zpsvuudyjpo.jpg

Another option to consider can be to use formulas to set a start no earlier after shutdown finish for all/selected activities whose start/finish would otherwise happen during the shutdown period.

Good luck.

Member for

18 years 11 months

Hi Vladimir,

You've caught me with sloppy language - MSP has no formal hammock or LOE tasks.  For "hammocks" that are created using "Paste Link" (OLE linking), the answer is yes, unfortunately.  That is, MSP can add a leveling delay to a hammock task that does not apply to its underlying source tasks.  This is silly - providing one more argument against OLE date links in a schedule.  I don't use them.

Summary tasks are never "leveled" (i.e. delayed by the leveler) according to my testing.  Any conflicting non-summary task, regardless of assigned priority, will be delayed.

Neither of these issues affects Paul's special case, in my view, since I have assumed that his shutdown interval will be fixed.

 

 

Member for

24 years 8 months

Tom,

does MS Project level hammocks?

Member for

18 years 11 months

Hi Paul,
 
Given that there are zero logical dependencies between the 25-day "non-splitable task" and the 4-week "Shutdown" period, then the only way I know to get what you want is to use the resource leveler.  i.e.
 
  1. Assign a common dummy resource to your "non-splitable task" and to a hammock or summary representing all the shutdown activities;
  2. Give your non-splitable task a lower priority than the shutdown hammock.  Then ensure that "Leveling order" in your resource leveling options is set to "Priority, Standard".
  3. Run the leveler as needed.

As a result, your 25-day "non-splitable task" will be scheduled according to its own logical drivers.  If these logical drivers allow sufficient time to complete the work before the start of the shutdown, then the 25-day task will proceed.  Otherwise it will be given a leveling delay to avoid the conflict with the shutdown period.

 
A couple notes:
 
  1. Interruptions that are caused by non-working time in a task's calendar should not be confused with technical task "splits," which are generally not related to calendars.
  2. Total slack and the "critical" flag can become meaningless or misleading in the presence of resource leveling.  If you depend on critical path analysis, then you would probably want to use logical ties rather than resource leveling here.  
 
Good luck, tmb