Summary
Environments that run a high volume of database transactions on a Microsoft SQL Server 2019 instance might produce severe spinlock contention. The contention is generally observed on high-end systems that use newer generation processors.
The following conditions can be observed regarding severe spinlock contention:
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Commonly observed on modern hardware, particularly Intel Skylake processors. It might also be observed on other modern processors.
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Usually observed on systems that have many processors.
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Environments might have more concurrent users, such as mission critical, highly transactional workloads.
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Symptoms include unexpectedly high CPU usage and many spins and backoff events for a particular spinlock type, and a higher number of spins per collision.
Status
Microsoft has confirmed that this is a problem in the Microsoft products that are listed in the "Applies to" section.
Resolution
The spinlock improvement was first made available in Cumulative Update 2 for SQL Server 2019. Additional improvements were made in the following cumulative updates for SQL Server:
We recommend that you apply the latest cumulative update in this list to address various spinlock contention issues.
Important: To be able to correct the spinlock issue, trace flag 8101 must be enabled after you apply one of the CUs from this list.
About cumulative updates for SQL Server
Each new cumulative update for SQL Server contains all the hotfixes and all the security fixes that were included with the previous cumulative update. Check out the latest cumulative updates for SQL Server:
Troubleshooting
To troubleshoot spinlock contention, see the following articles for in-depth information about how to identify and resolve problems that are related to high CPU and spinlock contention in SQL Server applications:
References
Learn about the terminology that Microsoft uses to describe software updates.
sys.dm_os_spinlock_stats (Transact-SQL) | Microsoft Learn
DBCC TRACEON - Trace Flags (Transact-SQL)
Third-party information disclaimer
The third-party products that this article discusses are manufactured by companies that are independent of Microsoft. Microsoft makes no warranty, implied or otherwise, about the performance or reliability of these products.
