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PWAIT_ALL_COMPONENTS_INITIALIZED

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Description:

Unknown, but I’m guessing from the call stacks that this wait type occurs during SQL Server startup for some background tasks while they initialize, for instance the SQL OS resource monitor (see Jonathan’s post here for more information).

(There is no Books Online description for this wait type.)

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Added in SQL Server version:

2012

Removed in SQL Server version:

N/A

Extended Events wait_type value:

Maps to the ALL_COMPONENTS_INITIALIZED map_value in sys.dm_xe_map_values (thanks to Jonathan’s post here).

The map_key value in sys.dm_xe_map_values is 733 in 2012 and 751 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:

I have not seen this wait type be a noticeable contention point.

This wait type is one that I usually filter out as a benign wait when doing wait statistics analysis.

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

  1. Waiting for the SQL OS resource monitor to initialize
  2. Waiting for the Extended Events subsystem to initialize

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

  1. SOS_Task::PostWait+9e
    EventInternal<SuspendQueueSLock>::Wait+23b
    SQLStartupShutdownControl::WaitForComponentsInitialized+59
    SetupResourceMonitorTaskContext+2d
    SOS_Task::Param::Execute+21e
    SOS_Scheduler::RunTask+ab
  2. SOS_Task::PostWait+9e
    EventInternal<SuspendQueueSLock>::Wait+23b
    SQLStartupShutdownControl::WaitForComponentsInitialized+59
    XESQLSetupThreadContext+79
    XE_Timer::EntryPoint+28
    SOS_Task::Param::Execute+21e
    SOS_Scheduler::RunTask+ab