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⏳Part of the SQL Server Wait Types Library, every wait type explained.Related deep dive: WRITELOG Wait TypeRelated pillar: Performance & Troubleshooting Is It a Problem? No. It is not a known contention point, and Get Wait Statistics filters it out by default. What It Means Microsoft does not list it in sys.dm_os_wait_stats. It is a…

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⏳Part of the SQL Server Wait Types Library, every wait type explained.Related deep dive: WRITELOG Wait TypeRelated pillar: Performance & Troubleshooting Is It a Problem? No. It is not reported as a contention point; it was zero on our SQL Server 2025 lab. Get Wait Statistics does not filter it out, so if it ranks,…

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⏳Part of the SQL Server Wait Types Library, every wait type explained.Related deep dive: HADR_SYNC_COMMIT Wait TypeRelated pillar: High Availability Is It a Problem? Short appearances during Availability Group changes are the mechanism working. It is documented as an expected wait, for Microsoft support’s use. It is worth a look only when one thread sits…

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⏳Part of the SQL Server Wait Types Library, every wait type explained.Related deep dive: IO_COMPLETION Wait TypeRelated pillar: Performance & Troubleshooting Is It a Problem? No. It is a Query Store background wait, it is commonly filtered as benign, and Get Wait Statistics filters it out by default. Its total grows wherever Query Store is…

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⏳Part of the SQL Server Wait Types Library, every wait type explained.Related deep dive: IO_COMPLETION Wait TypeRelated pillar: Performance & Troubleshooting Is It a Problem? No. It is the Query Store cleanup task’s sleep between runs, it is commonly filtered as benign, and Get Wait Statistics filters it out by default. On our SQL Server…

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⏳Part of the SQL Server Wait Types Library, every wait type explained.Related deep dive: RESOURCE_SEMAPHORE Wait TypeRelated pillar: Performance & Troubleshooting Is It a Problem? No. It is not reported as a contention point; it was zero on our SQL Server 2025 lab. Get Wait Statistics does not filter it out, so if it ranks,…

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⏳Part of the SQL Server Wait Types Library, every wait type explained.Related deep dive: IO_COMPLETION Wait TypeRelated pillar: Performance & Troubleshooting ⚡QDS_LOADDB is Query Store loading its data for a database as that database starts, after a restart, failover or recovery. On SQL Server 2016 and 2017 that load is synchronous by default and holds…

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⏳Part of the SQL Server Wait Types Library, every wait type explained.Related deep dive: IO_COMPLETION Wait TypeRelated pillar: Performance & Troubleshooting Is It a Problem? No. It is a Query Store background timer, commonly filtered as benign, and Get Wait Statistics filters it out by default. What It Means Microsoft lists it as internal use…

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⏳Part of the SQL Server Wait Types Library, every wait type explained.Related deep dive: RESOURCE_SEMAPHORE Wait TypeRelated pillar: Performance & Troubleshooting Is It a Problem? It can be, in one shape. On a very busy ad hoc workload, where most statements have unique text, registering new queries becomes a bottleneck and this wait becomes prevalent.…

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⏳Part of the SQL Server Wait Types Library, every wait type explained.Related deep dive: SOS_SCHEDULER_YIELD Wait TypeRelated pillar: Performance & Troubleshooting Is It a Problem? Normally no; it was zero on our SQL Server 2025 lab. Get Wait Statistics does not filter it out, so if it ranks, you will see it. The exception to…

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