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  • HADR_WORK_POOL Wait Type in SQL Server

    ⏳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? No. HADR_WORK_POOL is concurrency control inside the Availability Group background worker pool, and it is not reported as a contention point. Get Wait Statistics does not filter it out, so on…

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  • HADR_TIMER_TASK Wait Type in SQL Server

    ⏳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? No. HADR_TIMER_TASK is Availability Group timer bookkeeping, and most of its total is time spent waiting for the next run of a scheduled task. It is commonly filtered as benign, and…

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  • HADR_SEEDING_LIMIT_BACKUPS Wait Type in SQL Server

    ⏳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? It appears not. It is documented as internal use only, from SQL Server 2016, and the only description is anecdotal: long waits, thousands of seconds, for the length of some automatic…

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  • HADR_NOTIFICATION_DEQUEUE Wait Type in SQL Server

    ⏳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? No. It is commonly filtered as benign, and Get Wait Statistics filters it out by default. A large total means the cluster has been quiet. What It Means Microsoft’s definition: a…

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  • HADR_LOGPROGRESS_SYNC Wait Type in SQL Server

    ⏳Part of the SQL Server Wait Types Library, every wait type explained.Related deep dive: HADR_SYNC_COMMIT Wait TypeRelated pillar: High Availability ⚡HADR_LOGPROGRESS_SYNC is contention on the structure that releases synchronous commits on an Availability Group primary. When it becomes prevalent, HADR_SYNC_COMMIT rises with it even though the network and secondary look fine. Run the check to…

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  • HADR_LOGCAPTURE_WAIT Wait Type in SQL Server

    ⏳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? No. Microsoft calls it an expected wait if the log scan is caught up to the end of log or is reading from disk, and Get Wait Statistics filters it out…

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  • HADR_ARCONTROLLER and HADR_FILESTREAM_IOMGR Wait Types in SQL Server

    ⏳Part of the SQL Server Wait Types Library, every wait type explained.Related deep dive: HADR_SYNC_COMMIT Wait TypeRelated pillar: High Availability Two small Availability Group internals share this page. The definitions are Microsoft’s: HADR_ARCONTROLLER_NOTIFICATIONS_SUBSCRIBER_LIST: the publisher for an availability replica event, such as a state or configuration change, waiting for exclusive read/write access to the list…

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  • DBA Scripts: Get Temp DB Hotspots

    🔧Part of the DBA-Tools Project, copy/paste SQL Server scripts and health checks.In: Storage & Capacity Temp DB is shared by every database and every session on the instance: temp tables, table variables, sort and hash spills, version store for snapshot isolation, all of it lands in the same handful of files. When Temp DB is…

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  • HADR_GROUP_COMMIT Wait Type in SQL Server

    ⏳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? By design, no. Microsoft calls it an expected condition that optimizes the log I/O, capture, and send operations. Get Wait Statistics does not filter it out, so if it ranks, you…

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  • HADR_FILESTREAM_IOMGR_IOCOMPLETION Wait Type in SQL Server

    ⏳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? No. It is a timer, commonly filtered as benign, and Get Wait Statistics filters it out by default. What It Means Microsoft’s definition: the FILESTREAM Always On I/O manager is waiting…

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