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WAITFOR

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Description:

Just as the Books Online description says below.

(Books Online description: “Occurs as a result of a WAITFOR Transact-SQL statement. The duration of the wait is determined by the parameters to the statement. This is a user-initiated wait.”)

Questions/comments on this wait type? Click here to send Paul an email, especially if you have any information to add to this topic.

Added in SQL Server version:

Pre-2005/2005

Removed in SQL Server version:

N/A

Extended Events wait_type value:

The map_key value in sys.dm_xe_map_values is 189 in 2008 and 2008 R2, 195 in 2012, and 202 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, but if the WAITFOR wait type has the most accumulated wait time on your instance, you might want to check whether someone has accidentally left a debug WAITFOR statement in deployed code.

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. Running a WAITFOR statement

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

  1. SOS_Task::PostWait+9e
    SOS_Task::Sleep+195
    CStmtWait::XretExecute+2f5
    CMsqlExecContext::ExecuteStmts<1,0>+1782
    CMsqlExecContext::FExecute+a4a
    CSQLSource::Execute+86c
    process_request+a57
    process_commands+4a3
    SOS_Task::Param::Execute+21e
    SOS_Scheduler::RunTask+ab