(Republishing, or using this info in a commercial product/website, is prohibited without permission. All other uses are permitted. If in doubt, please ask.)
Description:
This wait type is when a thread is waiting for an In-Memory OLTP operation that was started by the regular Engine.
(Books Online description: “Occurs when waits are triggered by the database engine and implemented by the host.”)
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:
2014
Removed in SQL Server version:
N/A
Extended Events wait_type value:
Maps to the XTP_HOST_WAIT map_value in sys.dm_xe_map_values.
The map_key value in sys.dm_xe_map_values is 896 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:
This wait type is one that I usually filter out as a benign wait when doing wait statistics analysis.
I have not seen this wait to be a noticeable contention point.
Known occurrences in SQL Server (list number matches call stack list):
- Waiting for an In-Memory OLTP wait to end (in this case, when shutting down an In-Memory OLTP process after a failure)
Abbreviated call stacks (list number matches known occurrences list):
- SOS_Task::PostWait+9e
EventInternal<SuspendQueueSLock>::Wait+1fb
HkHostWait::Wait+ce
hkengine.dll!HkSetOfflineShutdownFlag+3f30b
HkHostReportFailure::KillProcess+372
SOS_Task::Param::Execute+21e
SOS_Scheduler::RunTask+a8