Occurs with parallel query plans when a consumer thread waits for a producer thread to send rows. Applies to: SQL Server (Starting with SQL Server 2016 (13.x) SP2, SQL Server 2017 (14.x) CU3), SQL Database Occurs with parallel query plans when synchronizing the query processor exchange iterator, and when producing and consuming rows.If waiting is excessive and cannot be reduced by tuning the query (such as adding indexes), consider adjusting the cost threshold for parallelism or lowering the degree of parallelism.Then, the worker waits to obtain the outcome of the distributed transaction that the worker is working on.This may continue until the connection with the MS DTC service has been reestablished.Note: Starting with SQL Server 2016 (13.x) SP2, SQL Server 2017 (14.x) CU3, and SQL Database, CXPACKET only refers to synchronizing the query processor exchange iterator, and to producing rows for consumer threads.Consumer threads are tracked separately in the CXCONSUMER wait type.If a mount operation is not pending, this wait type may indicate a hardware problem with the tape drive.
The data structure is locked to maintain its integrity if there is parallel access.
This state controls when the recovery of Microsoft Distributed Transaction Coordinator (MS DTC) transactions occurs after SQL Server receives notification that the MS DTC service has become unavailable.
Occurs in a MS DTC worker session when the session is waiting to take ownership of a MS DTC transaction.
Occurs during parallel queries while synchronizing in query processor in areas not related to the exchange iterator.
Examples of such areas are bitmaps, large binary objects (LOBs), and the spool iterator. Occurs when a full-text crawl needs to restart from a last known good point to recover from a transient failure.