Typically when you see OLEDB waits they come from querying linked servers set up through OLEDB. If you are seeing a high number of these as a query runs, you should consider monitoring performance on the remote server to see how the query on the local server splits the work up. Unfortunately the optimizer is […]
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ASYNC_NETWORK_IO Wait, What is it? What causes it?
You may occasionally see ASYNC_NETWORK_IO waits surface in your database . This wait can be caused by an unhealthy network connection; however, more often than not I see it caused for different reasons. What are causes of ASYNC_NETWORK_IO wait? There’s a few common scenarios I see as a cause for this. Queries retrieving large result […]
Read MoreHow to fix RESOURCE_SEMAPHORE waits
RESOURCE_SEMAPHORE waits occur when a query is unable to get enough memory to execute. In this post I will describe how to see they are occurring. I will also provide tips on ways to help reduce or eliminate them. How do I see them occurring? You can detect they are occurring by checking wait stats. […]
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