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SQL Server leverages MSDTC for distributed transactions (begin distributed transaction, remote proc trans, etc.) Prior to SQL Server 2016 the MSDTC service must be running (started) prior to any SQL Server, DTC based transaction activity.
SQL Server 2016 enhances SQL distributed transaction capabilities leveraging MSDTC, On Demand startup. The On Demand startup of MSDTC does not start the MSDTC service and consume resources until SQL Server requires MSDTC.
SQL Server 2016 extends the SQL Server DTC manager initialization logic allowing On Demand startup of the MSDTC service. (API Reference: DtcGetTransactionManagerEx) During the SQL Server, DTC manager initialization SQL Server 2016 attempts