| title | Access check cache Server Configuration Options | |||
|---|---|---|---|---|
| description | Learn about the access check result cache and the options that control the cache's behavior. See when to change these options in SQL Server. | |||
| author | rwestMSFT | |||
| ms.author | randolphwest | |||
| ms.reviewer | randolphwest | |||
| ms.date | 09/07/2022 | |||
| ms.prod | sql | |||
| ms.technology | configuration | |||
| ms.topic | conceptual | |||
| helpviewer_keywords |
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[!INCLUDE SQL Server]
When database objects are accessed by [!INCLUDEssNoVersion], the access check is cached in an internal structure called the access check result cache.
The access check cache bucket count option controls the number of hash buckets that are used for the access check result cache.
The access check cache quota option controls the number of entries that are stored in the access check result cache. When the maximum number of entries is reached, the oldest entries are removed from the access check result cache.
The default values of 0 indicate that [!INCLUDEssNoVersion] is managing these options. The default values translate to the following internal configurations.
[!INCLUDE sssql16-md] and later
| Server architecture | Default number of entries | |
|---|---|---|
| Access check cache quota | x64 | 1,024 |
| Access check cache bucket count | x64 | 256 |
[!INCLUDE sql2008-md] to [!INCLUDE sssql14-md]
| Server architecture | Default number of entries | |
|---|---|---|
| Access check cache quota | x86 | 1,024 |
| x64 and IA-64 | 28,192,048 | |
| Access check cache bucket count | x86 | 256 |
| x64 and IA-64 | 2,048 |
In rare circumstances, performance may be improved by changing these options. For example, you might want to reduce the size of the access check result cache if too much memory is used. Or, increase the size of the access check result cache if you experience high CPU usage when permissions are recalculated.
We recommend only changing these options when directed by Microsoft Customer Support Services. If you want to change the access check cache bucket count and access check cache quota values, use a ratio of 1:4. For example, if you change the access check cache bucket count value to 512, you should change the access check cache quota value to 2048.