SQL DBA Blog: Home

  • KSOURCE_WAKEUP Wait Type in SQL Server

    ⏳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? No. Microsoft says long waits are expected and don’t indicate a problem. Get Wait Statistics does not filter it out, so if it ranks, you will see it. In practice…

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  • IO_QUEUE_LIMIT Wait Type in SQL Server

    ⏳Part of the SQL Server Wait Types Library, every wait type explained.Related deep dive: IO_COMPLETION Wait TypeRelated pillar: Performance & Troubleshooting ⚡IO_QUEUE_LIMIT is commonly reported as I/O being throttled, most often by Azure SQL Database resource governance. It is documented only as internal use only, so treat that reading as community knowledge and confirm it…

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  • IMPPROV_IOWAIT Wait Type in SQL Server

    ⏳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? Only as much as your bulk loads need to be fast. During a load window it is expected; the question is whether the time per read is reasonable for where…

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  • HTREPARTITION Wait Type in SQL Server

    ⏳Part of the SQL Server Wait Types Library, every wait type explained.Related deep dive: CXPACKET and CXCONSUMER Wait TypesRelated pillar: Performance & Troubleshooting Is It a Problem? Usually not on its own; steady amounts on an analytics workload are the cost of batch mode. Get Wait Statistics does not filter it out, so if it…

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  • HTREINIT Wait Type in SQL Server

    ⏳Part of the SQL Server Wait Types Library, every wait type explained.Related deep dive: CXPACKET and CXCONSUMER Wait TypesRelated pillar: Performance & Troubleshooting Is It a Problem? Usually not on its own; steady amounts on an analytics workload are the cost of batch mode. Get Wait Statistics does not filter it out, so if it…

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  • HTMEMO Wait Type in SQL Server

    ⏳Part of the SQL Server Wait Types Library, every wait type explained.Related deep dive: CXPACKET and CXCONSUMER Wait TypesRelated pillar: Performance & Troubleshooting Is It a Problem? Usually not on its own; steady amounts on an analytics workload are the cost of batch mode. Get Wait Statistics does not filter it out, so if it…

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  • HTDELETE Wait Type in SQL Server

    ⏳Part of the SQL Server Wait Types Library, every wait type explained.Related deep dive: CXPACKET and CXCONSUMER Wait TypesRelated pillar: Performance & Troubleshooting Is It a Problem? Usually not on its own; steady amounts on an analytics workload are the cost of batch mode. Get Wait Statistics does not filter it out, so if it…

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  • HTBUILD Wait Type in SQL Server

    ⏳Part of the SQL Server Wait Types Library, every wait type explained.Related deep dive: CXPACKET and CXCONSUMER Wait TypesRelated pillar: Performance & Troubleshooting Is It a Problem? Usually not on its own; steady amounts on an analytics workload are the cost of batch mode. Get Wait Statistics does not filter it out, so if it…

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  • HP_SPOOL_BARRIER Wait Type in SQL Server

    ⏳Part of the SQL Server Wait Types Library, every wait type explained.Related deep dive: CXPACKET and CXCONSUMER Wait TypesRelated pillar: Performance & Troubleshooting Is It a Problem? If you can see it at all, the useful conclusion is about your build. It is not in Microsoft’s wait type list and does not exist on our…

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  • HADR_WORK_QUEUE 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 when there are ready workers waiting for new work, which it describes as the normal state. On an Availability Group instance it grows around…

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