SharePoint SPRequest Leak

Question

I have been getting this weird message in the ULS ever since I ported the code over to SharePoint 2010.

Here is the message:

w3wp.exe (0x1320)
0x1168 SharePoint Foundation
General
90hv
Unexpected

Detected use of SPRequest for previously closed SPWeb object. Please close SPWeb objects when you are done with all objects obtained from them, but not before.

Stack trace:
at Microsoft.SharePoint.SPWorkItem.FetchData()
at Microsoft.SharePoint.SPWorkItem.retrieveSchema(Schema schemaIndex)
at Microsoft.SharePoint.SPWorkItem.get_SiteId()
at Microsoft.SharePoint.SPWorkItem.Delete()
at Microsoft.SharePoint.Workflow.SPWinOeHostServices.WorkItemDequeue(Transaction txn, Object[] transData)
at Microsoft.SharePoint.Workflow.SPPendingWorkBatch.Commit(Transaction transaction, ICollection items)
at System.Workflow.Runtime.WorkBatch.PendingWorkCollection.Commit(Transaction transaction)
at System.Workflow.Runtime.WorkBatch.Commit(Transaction transaction)
at System.Workflow.Runtime.Hosting.WorkflowCommitWorkBatchService.CommitWorkBatch(CommitWorkBatchCallback commitWorkBatchCallback)
at System.Workflow.Runtime.Hosting.DefaultWorkflowCommitWorkBatchService.CommitWorkBatch(CommitWorkBatchCallback commitWorkBatchCallback)
at System.Workflow.Runtime.WorkflowExecutor.CommitTransaction(Activity activityContext)
at System.Workflow.Runtime.WorkflowExecutor.Persist(Activity dynamicActivity, Boolean unlock, Boolean needsCompensation)
at System.Workflow.Runtime.WorkflowExecutor.System.Workflow.ComponentModel.IWorkflowCoreRuntime.PersistInstanceState(Activity activity)
at System.Workflow.ComponentModel.Activity.MarkClosed()
at System.Workflow.ComponentModel.Activity.ReleaseLockOnStatusChange(IActivityEventListener1 eventListener) at System.Workflow.ComponentModel.FaultAndCancellationHandlingFilter.SafeReleaseLockOnStatusChange(ActivityExecutionContext context) at System.Workflow.ComponentModel.FaultAndCancellationHandlingFilter.OnEvent(Object sender, ActivityExecutionStatusChangedEventArgs e) at System.Workflow.ComponentModel.ActivityExecutorDelegateInfo1.ActivityExecutorDelegateOperation.Run(IWorkflowCoreRuntime workflowCoreRuntime)
at System.Workflow.Runtime.Scheduler.Run()
at System.Workflow.Runtime.WorkflowExecutor.RunScheduler()
at System.Workflow.Runtime.WorkflowExecutor.RunSome(Object ignored)
at System.Workflow.Runtime.Hosting.DefaultWorkflowSchedulerService.WorkItem.Invoke(WorkflowSchedulerService service)
at System.Workflow.Runtime.Hosting.ManualWorkflowSchedulerService.RunOne(Guid workflowInstanceId)
at System.Workflow.Runtime.Hosting.ManualWorkflowSchedulerService.RunWorkflow(Guid workflowInstanceId)
at Microsoft.SharePoint.Workflow.SPWinOeHostServices.Send(SPWorkflow workflow, SPWinOeWorkflow winoeworkflow, SPWorkflowEvent e)
at Microsoft.SharePoint.Workflow.SPWinOeEngine.RunWorkflow(SPWorkflowHostService host, SPWorkflow workflow, Collection1 events, TimeSpan timeOut) at Microsoft.SharePoint.Workflow.SPWorkflowManager.RunWorkflowElev(SPWorkflow workflow, Collection1 events, SPWorkflowRunOptionsInternal runOptions)
at Microsoft.SharePoint.Workflow.SPWorkflowManager.StartWorkflowElev(Object context, SPWorkflowAssociation association, DateTime elevationTimeUtc, SPWorkflowEvent startEvent, SPWorkflowRunOptions runOptions)
at Microsoft.SharePoint.Workflow.SPWorkflowAutostartEventReceiver.<>c_DisplayClass1.b_0(SPSite superUserSite, SPWeb superUserWeb)
at Microsoft.SharePoint.SPSecurity.<>c_DisplayClassf.b_e()
at Microsoft.SharePoint.SPSecurity.<>c_DisplayClass4.b_2()
at Microsoft.SharePoint.Utilities.SecurityContext.RunAsProcess(CodeToRunElevated secureCode)
at Microsoft.SharePoint.SPSecurity.RunWithElevatedPrivileges(WaitCallback secureCode, Object param)
at Microsoft.SharePoint.SPSecurity.RunWithElevatedPrivileges(CodeToRunElevated secureCode)
at Microsoft.SharePoint.Workflow.SPWorkflowAutostartEventReceiver.AutoStartWorkflow(SPItemEventProperties properties, Boolean bCreate, Boolean bChange, AssocType atyp)
at Microsoft.SharePoint.Workflow.SPWorkflowAutostartEventReceiver.ItemUpdated(SPItemEventProperties properties)
at Microsoft.SharePoint.SPEventManager.RunItemEventReceiver(SPItemEventReceiver receiver, SPUserCodeInfo userCodeInfo, SPItemEventProperties properties, SPEventContext context, String receiverData)
at Microsoft.SharePoint.SPEventManager.RunItemEventReceiverHelper(Object receiver, SPUserCodeInfo userCodeInfo, Object properties, SPEventContext context, String receiverData)
at Microsoft.SharePoint.SPEventManager.<>c_DisplayClassc`1.b_6()
at Microsoft.SharePoint.SPSecurity.RunAsUser(SPUserToken userToken, Boolean bResetContext, WaitCallback code, Object param)
at Microsoft.SharePoint.SPEventManager.InvokeEventReceivers[ReceiverType](SPUserToken userToken, Guid tranLockerId, RunEventReceiver runEventReceiver, Object receivers, Object properties, Boolean checkCancel)
at Microsoft.SharePoint.SPEventManager.InvokeEventReceivers[ReceiverType](Byte[] userTokenBytes, Guid tranLockerId, RunEventReceiver runEventReceiver, Object receivers, Object properties, Boolean checkCancel)
at Microsoft.SharePoint.SPEventManager.HandleEventCallback[ReceiverType,PropertiesType](Object callbackData)
at Microsoft.SharePoint.Utilities.SPThreadPool.WaitCallbackWrapper(Object state)
at System.Threading.ExecutionContext.runTryCode(Object userData)
at System.Runtime.CompilerServices.RuntimeHelpers.ExecuteCodeWithGuaranteedCleanup(TryCode code, CleanupCode backoutCode, Object userData)
at System.Threading.ExecutionContext.Run(ExecutionContextexecutionContext, ContextCallback callback, Object state)
at System.Threading._ThreadPoolWaitCallback.PerformWaitCallbackInternal(_ThreadPoolWaitCallback tpWaitCallBack)
at System.Threading._ThreadPoolWaitCallback.PerformWaitCallback(Object state)

This message comes up whenever I run the workflow, it does not appear to have any harmful effects to the workflow.

Please let me know anything you folks know.

As the error message states this kind of error is usually seen when you try to utilize an SPWeb instance after you had already closed/disposed it. Are you by any means creating SPWeb instance in your workflow code? Your issue can be caused from a reused instance somewhere in the code. That said, there are report of the Document Set class causing the same error on SP 2010, so it -could- be a bug in the Microsoft classes. — SPArcheon
I use SPWeb and SPSite in 'using' constructs so there should not be an issue for that. Furthermore I also use and NOT dispose web and site properties in the workflow properties. I am gravitating to your thing about the bug. Sigh...more log reading for me I guess. — Benjamin Wong
the stack trace seem to indicate that the closed instance is reused in the FetchData() SPWorkItem method. Problem is that it doesn't states where the instance was closed in first place. There should be a registry key that enables tracking for unclosed SPRequest objects, don't know if the opposite is also possible. — SPArcheon
I have decided to treat this as a weird internal bug or something. If I get back something I will update this. — Benjamin Wong

Jason Weber Jason Weber · Accepted Answer · 2011-11-23T06:12:21

Here's the guidance from MS around the proper disposal of SharePoint objects. Odds are good that if you're following all of these (correctly) then your code will be ok. The SPDisposeCheck tool can also be helpful, although in my exeprience you still need to know all of the disposal rules. This tool only does a static analysis and can return a lot of candidate issues that may actually be fine.

SharePoint SPRequest Leak

2 Answers