none
unexpected behavour of "fixed duration" in relation to holiday dates RRS feed

  • Question

  • I am used to planning in terms of both effort (how many man days will it take vs resources = duration) and Duration (how long will it take given the resources you have).  The current client prefers to use duration and then manipulate the resources being used to deliver the task to ensure that it delivers on time.  I mention this to preclude the "use effort" answer which is an obvious one :)

    I have a number of national resource calandars which are applied to resources to ensure that they are not being asked to deliver something on a public holiday.  In this case I am using the UK Calendar applied to the two resources in question.

    There is a 10 day task (propose) feeding into a single day task (accept).  Both tasks are Fixed Duration (effort drive) so all very normal.  What is confusing is that the 10 day task is shown as finishing on the 4th June (Bank Holiday) and the accept task is the 5th with 0d effort even though the rosource is 100% applied.

    Shortening the duration of the propose task to 9 days triggers an error telling me that the Accept task has resources assigned outside the original dates and that it is changing the duration - to 2 days.  This results in the assign task having 2 duration and 1 day work and finishing on the 6th (after the two day holiday).  Oddly when I bump the Propose task back up to 10 days the approve remains at 2 days and is now finishing onthe 7th.!

    All in all this behaviour is counter to what I expect i.e.:

    "Propose" is 10 days - 1 of these falls into a bank holiday - so that day should be moved to after the holiday - i.e. it should finish on the 6th and then Approve follows that.

    If Propose is cut to before the holiday "accept" should not happen in the midst of the holiday - it should be shown as being the daya after the holiday.  Project should not be adding days into the schedule to deal with the error and then not taking them out when the clash is removed by the schedule changing.

    Do I have a know system issue which can be fixed with a patch or is this user error and I have missed something that has changed in the migration to 2010 or have I got something set wrong?

    Many thanks

    Miles

    Monday, February 20, 2012 1:41 PM

Answers

  • Hi Miles,

    As far as I know, the issue with Fixed Duration tasks and resource non-working time has been around for a long time.  I have notes in material I wrote for Project 2003 with just this issue. I don't believe it is an issue of "10 days was 10 days in calendar time".

    If you create a simple 5 day task - set it as fixed duration and assign a resource -- assuming 100% assignment units you'll see 40 hours of work.

    If you change the resource's calendar after assigning, you'll get the message you note - the duration will increase to accommodate the changed working calendar.  If you replace the resource with one without non-working time -- the task will not re-adjust and you'll still see the trailing split.  My suggestion is if you experience this issue -- set the task back to Fixed Units and let Project remove the trailing split.

    However, if you change the resource calendar before assigning them to the fixed duration task, project just calculates the correct amount of work.

    I hope this helps.

    Julie

    Monday, February 20, 2012 3:11 PM
    Moderator

All replies

  • Hello Miles,

    Fixed Duration tasks are just that -- once the duration is modified -- it stays "stuck" there.  As far as the task finishing on a holiday in the resource calendar -- is there actually any work scheduled on that day -- take a look at the Task Usage view.

    Do you also have resources who do have working time on the holiday assigned?

    Using Fixed Duration, effort driven tasks has likely also decreased the resource assignment units but they will not show nicely in the Task Form.  Add Peak Units to the timescaled portion of the Task Usage view to see actual assignment values.

    Monday, February 20, 2012 2:29 PM
    Moderator
  • Julie

    No work is scheduled during the resources "holdiay" calendar however when they read the schedule they get stressed as it looks like they are going to have to do some work during their leave (as they will not be going into the resource or task usage views).

    I don't have a 2003 copy of project with me here however I am sure that previously fixed duration only related to the behavour of the Effort / Duration / Assignment triangle rather than demanding the 10 days was 10 days in calandar time - i.e. it took account of non working time like weekends so it could vary between 12 elapsed days and 14 elapsed days on a normal 5 day week and even longer if holidays were involved.  Has this changed and if so is there any way of getting back to the sort of behavour that users are used to?

    Interestingly if I assign another resoure without the holiday calendar to the task, hit return and then replace the dummy resource with the correct one the task behaves much more as expected.  Very strange... Edited to add - ignore this; I failed to spot that the new task went in "fixed units", sorry about the red herring :)

    Many thanks

    Miles


    • Edited by MilesS2111S Monday, February 20, 2012 2:55 PM
    Monday, February 20, 2012 2:54 PM
  • Hi Miles,

    As far as I know, the issue with Fixed Duration tasks and resource non-working time has been around for a long time.  I have notes in material I wrote for Project 2003 with just this issue. I don't believe it is an issue of "10 days was 10 days in calendar time".

    If you create a simple 5 day task - set it as fixed duration and assign a resource -- assuming 100% assignment units you'll see 40 hours of work.

    If you change the resource's calendar after assigning, you'll get the message you note - the duration will increase to accommodate the changed working calendar.  If you replace the resource with one without non-working time -- the task will not re-adjust and you'll still see the trailing split.  My suggestion is if you experience this issue -- set the task back to Fixed Units and let Project remove the trailing split.

    However, if you change the resource calendar before assigning them to the fixed duration task, project just calculates the correct amount of work.

    I hope this helps.

    Julie

    Monday, February 20, 2012 3:11 PM
    Moderator