index > Windows Workflow Foundation > Dynamic Updates/ApplyWorkflowChanges and Performance issues

Dynamic Updates/ApplyWorkflowChanges and Performance issues

We are using dynamic updates and we are experiencing some performance issues. Basically we have workflow templates with hooks, wich are extensibility points to inject before we run the workflow. When we receive a message, we inspect it, and the handler decide what template to use to serve this message. Then, we read a configuration file to get the activities to inject in the template workflow. After hooks injection we start the workflow.

The code we are using to do the dynamic updates is something like this

private static void InjectHooks(WorkflowInstance workflowInstance, MasterWorkflowElement masterConfiguration,
WorkflowElement workflowConfiguration)
{
Activity workflowRoot = workflowInstance.GetWorkflowDefinition();
WorkflowChanges workflowChanges = new WorkflowChanges(workflowRoot);
CompositeActivity transientWorkflow = workflowChanges.TransientWorkflow;

foreach (NamedConfigurationElement registeredHook in masterConfiguration.RegisteredHooks)
{
SequenceActivity hook = transientWorkflow.GetActivityByName(registeredHook.Name) as SequenceActivity;
Debug.Assert(hook != null, "hooks is null");

InjectedHookElement hookToInject = workflowConfiguration.HooksToInject.Get(registeredHook.Name);
if (hookToInject != null)
{
Activity hookActivity = (Activity) Activator.CreateInstance(
Type.GetType(hookToInject.HookTypeName), true) ;
Debug.Assert(hookActivity != null, "hookActivity is null");
hook.Activities.Add(hookActivity);
}
}

workflowInstance.ApplyWorkflowChanges(workflowChanges);
}

We are profiling our application using VSTS profiler instrumentation method. 10% (% Elapsed Inclusive Time) of the time is spent in the method ApplyWorkflowChanges.

The main question is if there something wrong with the design we choosed. Is there a way to have a kind of a prepared workflow, cache it, and clone it when the message arrives? Any ideas?

Thanks in advance

BFC

We already did some optimizations in our system. However we continue with the performance problem of the dynamic updates. Now the % Elapsed Inclusive Time increases to 45% (due to optimizations on the other parts of the system). This means that in every request we double the response time due off dynamic updates. We already know that dynamic updates are bad but we will apreciate some help in design alternatives to dynamic updates. We will release the 1st version of our system this month.

Please Help.

Thanks in advance

BFC

reply 2