hammock vs summary task

[KingKikapu]

Hello folks

I have a bit of an issue: I am currently using a large number of
hammock tasks (the linked field kind) in my project files (designed to
capture any costs that cannot be easily broken down by the related
sub-tasks). As an example, I have a Framing hammock that captures any
material costs that cannot easily be placed on the individual floor
framing tasks. Now, I am also running an Earned Value system that is
duration based, so these hammock tasks definitely have an associated
planned value at any given moment. The problem is that I now have
something of around 15-20 hammock tasks on every building project file,
and when these files are accessed remotely, I find it takes 10-20
minutes to load the bloody file (I am using MSP 2007 Pro, and that is
not changing anytime soon).

I need to do something about this. I have two choices available to me:
I can either run a terminal system back to the home server (thereby
technically running the file from the source and removing the 10-15
minute lag) or I can apply the resources that were intended for the
hammock onto the summary task that best matches.

I know that's considered bad form, but I don't quite understand why.
Could someone explain to me how that would mess things (mostly EVM) up?
Suggestions?

Thanks as always.

 

[Jim Aksel]

I would use the terminal server approach. We had the exact same problem
about a year ago, the issue is that project keeps wanting to recalculate
every time you hit the enter key (and when it loads) and that causes another
server call. So, it gets very slow.

You may want to try using a manual calculation mode then then hit F9 once it
all loads. That might speed it up a little bit as well. Then you could turn
on Autocalc once it is all loaded. That defeats the purpose, I guess...

On to your question. With resources loaded on summaries, you are going to
give the impression your costs and EV are not rolling up properly. The
summaries will appear over stated. That's a first look. Since Summary Task
Resources is not a technique I use, I haven't really explored what gremlins
are summoned by such naughtiness. A quick check with a three task file looks
like it does not hurt the EV calculations, just gives them an overstated
appearance and that is explainable by your deliberate action to assign
resources to summaries.

For certain, any assigned resources at both the detail and summary levels
are going to drive your resource loading curves and you may have leveling
nightmares or false overloading.

Keep in mind that summary tasks are intended to be for human understanding
and are not really tasks at all.

You may want to continue with the hammock tasks immediately under the
summary. As a suggestion, you can use the summary task start/finish dates to
drive you hammocks ... but you can see how this is a "recursive" type issue
on the calculation. This is becuase the summary task dates must be
calculated first base on their subordinate detail.

50% of the hammock may be avoidable. Try using a start date on the Hammock
of (Summary SS). You can then eliminate the start link and just use
SummaryFinish as the link to HammockFinish.


--
If this post was helpful, please consider rating it.

Jim Aksel, MVP

Check out my blog for more information:
http://www.msprojectblog.com

 

[Steve House]

Are you sure your hammock tasks are actually needed? The Fixed Cost field
of a summary task is one the few summary fields that is actually editable.
When you enter a value in it, it is added to the total summary cost over and
above the sum of the fixed and resource costs of the subtasks. Imagine a
Summary with 3 subtasks. Each subtask has $100 resource cost (work plus
material) plus $50 fixed cost. The summary task also has $100 in its own
Fixed Cost field. The summary task total cost will be 3*$150 plus $100 or
$550. Doesn't this accomplish what you're trying to do with the hammock
tasks, and without the other distortions they introduce?

 

[A-Saleh]

Hi,

In many cases I need to use hammock tasks especially when I need to assign a
group of resources (team) to do a list of tasks say 3; we do it this way to
optimize time and resources utilization; since, progress in any single task
might be interrupted by varies reasons. Practically, I wouldn't know who will
be doing what and when at any point in time but I do know that the team will
work on the list of tasks for say 3 days, in this example is there better way
to model it other than using hammock tasks?

 

[Rob Schneider]

I would think hammock tasks are only used for convience when you have to
"string" the task across two end points, e.g. including a "task" for
"project management" that stretches across the start and end of the
entire project.

If I understand what you are trying to do, I would think that this
should be scheduled into the part of the project where it makes sense,
e.g. the appropriate predecessors/successors.

--rms

www.rmschneider.com

 

[Steve House]

No offense intended but as PM why DON'T you know which resource will be
doing what when? It's the job of the PM to tell the resources what they
need to be doing and when they need to be doing it in order to drive the
project forward to complete on time and within budget, not the other way
around. That's reason "management" is part of the title. It's your job to
optimize the right resource's deployment on the right tasks at the right
time, not theirs. Hammock tasks don't get around that. All they do is
disguise the problem.