tracker issue : CF-3983192

Under only moderate load, we get pairs of stuck threads due to trying to duplicate() a shared object in a CFC.
To prevent this, we use a named CFLOCK to single thread requests.
However, some times we still see pairs (or more !) of threads blocking each other.

Below is a code snippet from the effected CFLOCK, and partial stack traces from FusionReactor clearly showing two requests inside the CFLOCK at once.
Both these threads were launched within two seconds of each other, so inside the timeout value.

Thread one stack trace from Fusion Reactor:
cfWidgetManager2ecfc842561472$funcWIDGETDATA.runFunction(/wwwroot/Branded/Default/reports3.0/com/ev/service/WidgetManager.cfc:307)
coldfusion.runtime.UDFMethod.invoke(UDFMethod.java:487)
coldfusion.filter.SilentFilter.invoke(SilentFilter.java:47)
coldfusion.runtime.UDFMethod$ArgumentCollectionFilter.invoke(UDFMethod.java:383)
coldfusion.filter.FunctionAccessFilter.invoke(FunctionAccessFilter.java:95)
coldfusion.runtime.UDFMethod.runFilterChain(UDFMethod.java:334)
coldfusion.runtime.UDFMethod.invoke(UDFMethod.java:533)
coldfusion.runtime.CfJspPage._invokeUDF(CfJspPage.java:2810)
cfWidgetManager2ecfc842561472$funcGETDATAFORUSERCAMPAIGN.runFunction(/wwwroot/Branded/Default/reports3.0/com/ev/service/WidgetManager.cfc:40)

Thread two stack trace from Fusion Reactor:
coldfusion.runtime.Struct.duplicate(Struct.java:153)
 - locked <0x18bf2bf> (a coldfusion.runtime.Struct)
coldfusion.runtime.ObjectDuplicator._duplicate(ObjectDuplicator.java:102)
coldfusion.runtime.ObjectDuplicator.duplicate(ObjectDuplicator.java:78)
coldfusion.runtime.TemplateProxy.duplicateScope(TemplateProxy.java:2567)
coldfusion.runtime.TemplateProxy.duplicate(TemplateProxy.java:2542)
coldfusion.runtime.ObjectDuplicator._duplicate(ObjectDuplicator.java:125)
coldfusion.runtime.ObjectDuplicator.duplicate(ObjectDuplicator.java:78)
coldfusion.runtime.TemplateProxy.duplicateScope(TemplateProxy.java:2567)
coldfusion.runtime.TemplateProxy.duplicate(TemplateProxy.java:2542)
coldfusion.runtime.ObjectDuplicator._duplicate(ObjectDuplicator.java:125)
coldfusion.runtime.ObjectDuplicator.duplicate(ObjectDuplicator.java:78)
coldfusion.runtime.CFPage.Duplicate(CFPage.java:6254)
cfWidgetFactory2ecfc1291701710$funcCREATEINSTANCE.runFunction(/wwwroot/Branded/Default/reports3.0/com/ev/factory/WidgetFactory.cfc:29)

Code block with line numbers 
27	        <cflock name="WidgetFactory-createInstance-#cgi.server_name#" timeout="30">
28	        <cfif StructKeyExists( variables.widgetInstances, arguments.widgetClass )>
29	                <cfset var o = duplicate( variables.widgetInstances[ arguments.widgetClass ] )/>
30	                <cfset o = o.init( variables.ormHelper.getClientDSN(this),
31	                                                variables.ormHelper.getDsn('scheduler')
32	                                         ) />
33	        <cfelse>
34	                <cfset var functionIndex=0>
35	                <cfset var o = CreateObject('component', arguments.widgetClass).init(
36	                                                                        variables.ormHelper.getClientDSN(this),
37	                                                                        variables.ormHelper.getDsn('scheduler')
38	                                                                         ) />
39	                <!--- from ColdSpring's DefaultXmlBeanFactory --->
40	                <cfset var md=variables.beanFactory.flattenMetaData(GetComponentMetaData(widgetClass))>

----------------------------- Additional Watson Details -----------------------------

Watson Bug ID:	3983192

External Customer Info:
External Company:  
External Customer Name: Tom
External Customer Email:  
External Test Config: CF11 fully updated on latest JVM 1.8, CentOS 5 32bit

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