Parallel Activity issue in Sequence Workflow

Parallel Activity issue in Sequence Workflow

• Jet Stream

  Notre,

  Thanks for pointing this out...I've logged an issue to get this corrected in the documentation.

  If it helps, here's the pseudo code for how the Parallel executes -
  
  ActivityExecutionStatus Execute(ActivityExecutionContext context)

     foreach(Activity child in this.EnabledActivities)
     {
        register for child's closed status change
        context.ExecuteActivity(child)
     }

  ...

   

  No additional threads are created.  All the children of the parallel are only scheduled for execution.

  Hope this helps!

  Arjun

  
  

• Ian Cummings

  Ganesan,

  This is true - if your scenario doesn't have any nondeterministic activities (i.e. EventSinks that are waiting for some user input), it'll probably run in the same order every time. You shouldn't, however, make any dependencies on the execution order of the parallel.

  
  

• root2

  Arjun,

  Thanks for that information.

  Then, i hope that parallel activity can be renamed into more meaningful like "Independent activities" in release version.

  I ran that test many more times, but order of execution did not change even once.

   

  Regards,

  Ganesan Krishnamurthy.

   

   

  
  

• gallileo

  Ganesan,

  Each workflow instance runs in a single thread.  The parallel activity does not guarantee the order in which it executes its children, but they will not run concurrently.  The parallel construct is particularly useful when you have branches that are blocked waiting for an event or a timer.  For true execution parallelism, you would need to create a new workflow instance and invoke it.

  Arjun

  
  

• Dawnyy

  Hmm.  This is confusing.  According to the Beta 1.2 docs at

  ms-help://MS.WinWF.v1.EN/WinWF_GettingStarted/html/86722377-f04d-4b25-bf50-b26765b79798.htm

  :

  The Parallel activity provides a mechanism by which two or more different actions can take place concurrently but independently

  There is also talk about synchronization of data access.

  Notre

  
  
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