[cvs] [Wiki] changed: Project/WorkflowApplication

[Chuck Hagenbuch]

chuck  Wed, 02 Apr 2008 23:12:14 -0400

Modified page: http://wiki.horde.org/Project/WorkflowApplication
New Revision:  1.4
Change log:  fold in info

@@ -1,4 +1,6 @@
+[[toc]]
+
 + Workflow Module

 Rough-cut task list for getting a minimal workflow module running for work
order use:

@@ -16,8 +18,38 @@
 || Implement e-mail decision "application" || 2.0 || NOT DONE ||
 || Implement work item history logging mechanism || 2.0 || NOT DONE ||
 || **Total** || 32.0 || ||

-Some relevant links:
+++ Workflow versus project management
+
++++ Project Management
+
+In project management tools, the project is represented by a directed graph
of dependant tasks.  There are no cycles or decision logic in a PERT chart,
and necessarily so because project management requires finding the length of
the timewise longest dependency path (the critical path) and resolving
resource contention, and both of these would be extremely difficult if not
impossible if we could not determine the project path ahead of time.
+
+In project management, therefore, lots of effort is expended up front in
the planning phase to remove these decision points. During the course of a
project, a change requires refactoring the dependency graph (the PERT
chart), which will affect the critical path and the project deadline.  It
can also cause reallocation of resources.
+
++++ Workflow
+
+In workflow, workitems contain a number of steps.  Workflow is built like a
state machine, and has built in decision logic.  A work item can cycle (e.g.
do step A, then do step B, then check if passes Q.C., if not, go back to
step B), has decision logic (if some test passes, do A, otherwise do B).  In
this model, we cannot predict the path.
+
++++ Goals
+
+* I would like to be able to apply the Wiki:TheoryOfConstraints to the
management of both workflow and projects
+* I would like unified resource management, or at least coopeartive
resource management between projects and workflow.
+* I would like to be able to have workflow items as project tasks.
+
++++ Problems
+
+* Resource management is difficult with workitems because the resources
required by a workitem may not be predictable until the workitem is running.
+* Estimating the time a workitem will run is difficult because it may have
a cycle.
+
++++ Possible Solutions
+
+* Workflow definition would constrain the time a workitem can run (to
counter cycles)
+* Scheduler would make sure all resources which might be required for a
workitem are available (costly).
+* Scheduler could predict based on past performance (error-prone)
+* User could hint at which cases are more likely.
+
+++ Resources

 * [http://sourceforge.net/projects/pear-workflow PEAR Workflow project]
 *
[http://kngforge.uwc.ac.za/KEWL.NextGen-Documentation/whitepapers/workflow_engine/workflow.doc Word doc on a workflow engine for Kewl.  Lots of nice references.]