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HADR_SYNC_COMMIT Wait Stats: Availability Group Commits

HADR_SYNC_COMMIT wait stats measure how long a commit waits for a synchronous secondary replica to harden the log. On Night 22 at the Clipboard Diner, every sale is phoned to a sister diner before the plate can leave. Learn what the wait includes, how to read the send and redo queues, and the fixes from the secondary’s log disk to asynchronous commit.

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ASYNC_NETWORK_IO Wait Stats: When the Application Is Slow

ASYNC_NETWORK_IO wait stats mean SQL Server has results ready and is waiting for the application to read them. On Night 21 at the Clipboard Diner, hot plates pile up at the pass while Quinn tells a long story at table 4. Learn the causes in the order I find them, two queries that name the slow program, and why the fixes live in the application.

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MSQL_XP Wait Stats: Extended Procedures and External Code

MSQL_XP wait stats measure the time a query waits while an extended stored procedure such as xp_cmdshell or xp_dirtree runs. On Night 20 at the Clipboard Diner, an outside caterer takes over one station behind a curtain. Then two queries show you which session is waiting and which procedure it called, and the fixes move that work outside SQL Server.

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