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PREEMPTIVE_OS_LOOKUPACCOUNTSID

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Description:

This wait type is when a thread is calling the Windows LookupAccountSid function.

(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 381 in 2008 and 2008 R2, 429 in 2012, and 445 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 servers that provide security authentication and authorization, such as Active Directory Controllers and 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. Looking up an account SID (in this case, when building the login token for a new client connection)

And other similar call stacks.

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

  1. SOS_Task::PopWait+b1
    SOS_ExternalAutoWait::~SOS_ExternalAutoWait+7c
    NTGroupInfo::`vector deleting destructor’+70b
    CSECWinLoginTokenBuilder::BuildLoginToken+3fb
    CSECWinLoginTokenBuilder::CallBuildLoginToken+6e
    CSECLoginTokenBuilder::CreateAndAuthorizeLoginToken+484
    FindLogin+3f6
    login+829
    process_login_finish+16e
    process_commands+456
    TDSSNIClient::AddSSPIProviderHandler+474
    TDSSNIClient::AddProviderHandler+38
    SNIProcessAddProviderOnWorker+122
    SOS_Task::Param::Execute+21e
    SOS_Scheduler::RunTask+ab