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PREEMPTIVE_OS_DOMAINSERVICESOPS

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Description:

This wait type is a generic wait for when a thread is calling one of several Windows functions related to domain services (e.g. creating and deleting SPNs).

(Books Online description: N/A)

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Added in SQL Server version:

2008

Removed in SQL Server version:

N/A

Extended Events wait_type value:

The map_key value in sys.dm_xe_map_values is 434 in 2008 and 2008 R2, 482 in 2012, and 498 in 2014 RTM. After 2014 RTM, you must check the DMV to get the latest value as some map_key values have changed in later builds.

Other information:

If you see long waits for this wait type, have your infrastructure team investigate performance issues with Domain Controllers.

Note that when a thread calls out to Windows, the thread changes from non-preemptive (SQL Server controls the thread) to preemptive (Windows controls the thread) mode. The thread’s state will be listed as RUNNING, as SQL Server doesn’t know what Windows is doing with the thread.

Known occurrences in SQL Server (list number matches call stack list):

  1. Removing an SPN from the Domain

And other similar stacks.

Abbreviated call stacks (list number matches known occurrences list):

  1. SOS_Task::PopWait+b1
    SOS_ExternalAutoWait::~SOS_ExternalAutoWait+7c
    SNI_Spn::AddRemoveSpn+794
    SNISecAddSpn+537
    TDSSNIClient::AddSPNWorker+10
    SOS_Task::Param::Execute+21e
    SOS_Scheduler::RunTask+ab