Description
Occurs while query memory requests cannot be granted due to other concurrent queries. High values of this wait type may indicate excessive number of concurrent queries, or excessive memory requests
Resolved by
DBAs and Developers
Suggested solutions
- Ensure that statistics are up to date
- Run a trace/Profiler/Extended Event session along with Windows Performance Monitor to determine which queries require an excessive amount of memory
- Indexing, look for high duration queries with large sorts and hash joins
- If possible rewrite queries to avoid large UNION, DISTINCT and ORDER BY operations
- Increase the maximum memory allocation
Additional research
Troubleshooting SQL Server RESOURCE_SEMAPHORE
Resource_semaphore wait type when using SORT