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Description:
This wait type is when a thread switches to preemptive mode as part of communicating with an OLE DB provider.
(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 473 in 2008 and 2008 R2, 521 in 2012, and 537 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.
Known occurrences in SQL Server (list number matches call stack list):
- Waiting for OLE DB information (in this case, while parsing/algebrizing a BULK INSERT statement during compilation)
- Waiting for OLE DB information (in this case, while parsing/algebrizing a query during compilation)
And other similar call stacks.
Abbreviated call stacks (list number matches known occurrences list):
- SOS_Task::PopWait+ba
AutoSwitchPreemptive::~AutoSwitchPreemptive+6e
COledbRangeStream::DoNormalize+359
COledbRange::Normalize+78
CStmtInsertBulk::FCompile+a6e
CStatement::FDoCompile+70
CCompPlan::FCompileStep+28a
CSQLSource::FCompile+105f
CSQLSource::FCompWrapper+c1
CSQLSource::Transform+4de
CSQLSource::Execute+449
process_request+64b
process_commands+4e5
SOS_Task::Param::Execute+12a - SOS_Task::PopWait+b1
SOS_ExternalAutoWait::~SOS_ExternalAutoWait+7c
COledbRangeStream::DoNormalize+663
COledbRange::Normalize+147
CAlgTableMetadata::FPartialBind+47a
CAlgTableMetadata::Bind+31d
CRelOp_Get::BindTree+429
COptExpr::BindTree+85
CRelOp_FromList::BindTree+37
COptExpr::BindTree+85
CRelOp_GroupBy::BindTree+58
COptExpr::BindTree+85
CRelOp_QuerySpec::BindTree+e9
COptExpr::BindTree+85
CRelOp_SelectQuery::BindTree+80
COptExpr::BindTree+85
CRelOp_Query::FAlgebrizeQuery+438
CProchdr::FNormQuery+55
CProchdr::FNormalizeStep+2e4
CSQLSource::FCompile+108a
CSQLSource::FCompWrapper+dd
CSQLSource::Transform+445