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Clarify REQUEST_MAX_CPU_TIME_SEC behavior in SQL MI
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‎docs/relational-databases/event-classes/cpu-threshold-exceeded-event-class.md‎

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description: "CPU Threshold Exceeded Event Class"
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author: WilliamDAssafMSFT
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ms.author: wiassaf
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ms.date: "03/04/2017"
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ms.date: 01/13/2025
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ms.service: sql
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ms.subservice: supportability
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ms.topic: reference
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helpviewer_keywords:
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- "CPU Threshold Exceeded Event Class"
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monikerRange: "=azuresqldb-current||>=sql-server-2016||>=sql-server-linux-2017||=azuresqldb-mi-current"
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---
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# CPU Threshold Exceeded Event Class
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# CPU threshold exceeded event class
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[!INCLUDE [SQL Server Azure SQL Database Azure SQL Managed Instance](../../includes/applies-to-version/sql-asdb-asdbmi.md)]
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The CPU Threshold Exceeded event class indicates that Resource Governor detects a query that exceeds the CPU threshold specified for REQUEST_MAX_CPU_TIME_SEC.
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> [!NOTE]
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> The detection interval for this event is five seconds. It is guaranteed that an event will be generated if a query exceeds the specified limit by at least five seconds. However, if a query exceeds the specified threshold by less than five seconds, its detection might be missed depending on the timing of the query and the time of last detection sweep.
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## CPU Threshold Exceeded Data Columns
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|Data column name|Data type|Description|Column ID|Filterable|
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|----------------------|---------------|-----------------|---------------|----------------|
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|CPU|**int**|CPU usage in milliseconds.|18|Yes|
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|EventClass|**int**|214|27|No|
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|EventSubClass|**int**|CPU limit violation.|21|Yes|
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|GroupID|**int**|Group ID where the violation occurred.|66|Yes|
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|OwnerID|**int**|SPID of the process that caused the violation.|58|Yes|
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|SPID|**int**|ID of the server process that fires this event.<br /><br /> Note: This can differ from the actual user SPID if a system thread validates CPU usage as a background task.|12|Yes|
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|StartTime|**datetime**|The time when this event fired.|14|Yes|
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## See Also
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[sp_trace_setevent &#40;Transact-SQL&#41;](../../relational-databases/system-stored-procedures/sp-trace-setevent-transact-sql.md)
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The **CPU threshold exceeded** event class indicates that resource governor detected a batch request that exceeds the CPU threshold specified for the `REQUEST_MAX_CPU_TIME_SEC` argument of a [workload group](../resource-governor/resource-governor-workload-group.md). For more information, see [CREATE WORKLOAD GROUP](../../t-sql/statements/create-workload-group-transact-sql#request_max_cpu_time_sec--value).
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## CPU threshold exceeded data columns
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| Data column name | Data type | Description | Column ID | Filterable |
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|:--|:--|:--|:--|:--|
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| CPU | **int** | CPU usage in milliseconds.| 18 | Yes |
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| EventClass | **int** | 214 | 27 | No |
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| EventSubClass | **int** | CPU limit violation. | 21 | Yes |
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| GroupID | **int** | Group ID where the violation occurred. | 66 | Yes |
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| OwnerID | **int** | SPID of the process that caused the violation. | 58 | Yes |
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| SPID | **int** | ID of the server process that fires this event.<br /><br /> Note: This can differ from the actual user SPID if a system thread validates CPU usage as a background task. | 12 | Yes |
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| StartTime | **datetime** | The time when this event fired. | 14 | Yes |
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## Related content
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- [sp_trace_setevent](../../relational-databases/system-stored-procedures/sp-trace-setevent-transact-sql.md)
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- [Resource governor](../../relational-databases/resource-governor/resource-governor.md)
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- [Resource governor workload group](../../relational-databases/resource-governor/resource-governor-workload-group.md)
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- [Create a workload group](../../relational-databases/resource-governor/create-a-workload-group.md)
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- [CREATE WORKLOAD GROUP](../statements/create-workload-group-transact-sql.md)
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- [ALTER WORKLOAD GROUP](../statements/alter-workload-group-transact-sql.md)
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‎docs/t-sql/includes/alter-workload-group.md‎

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author: rwestMSFT
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ms.author: randolphwest
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ms.reviewer: dfurman
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ms.date: 01/01/2025
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ms.date: 01/13/2025
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ms.service: sql
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ms.topic: include
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---
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#### REQUEST_MAX_CPU_TIME_SEC = *value*
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Specifies the maximum amount of CPU time, in seconds, that a request can use. *value* must be 0 or a positive integer. The default setting for *value* is 0, which means unlimited.
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Specifies the maximum amount of CPU time, in seconds, that a batch request can use. *value* must be 0 or a positive integer. The default setting for *value* is 0, which means unlimited.
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By default, resource governor doesn't prevent a request from continuing if the maximum time is exceeded. However, an event is generated. For more information, see [CPU Threshold Exceeded Event Class](../../relational-databases/event-classes/cpu-threshold-exceeded-event-class.md).
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When the maximum CPU time is exceeded, the `cpu_threshold_exceeded` extended event and a trace event are generated. For more information, see [CPU Threshold Exceeded Event Class](../../relational-databases/event-classes/cpu-threshold-exceeded-event-class.md).
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Starting with [!INCLUDE [sssql16-md](../../includes/sssql16-md.md)] SP2 and [!INCLUDE [sssql17-md](../../includes/sssql17-md.md)] CU3, and using [trace flag 2422](../database-console-commands/dbcc-traceon-trace-flags-transact-sql.md#tf2422), resource governor aborts a request when the maximum CPU time is exceeded.
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In Azure SQL Managed Instance, when the maximum CPU time is exceeded, resource governor aborts the request with error 10961.
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In [!INCLUDE [ssnoversion-md](../../includes/ssnoversion-md.md)], resource governor doesn't abort the request by default. However, starting with [!INCLUDE [sssql16-md](../../includes/sssql16-md.md)] SP2 and [!INCLUDE [sssql17-md](../../includes/sssql17-md.md)] CU3, resource governor aborts a request with error 10961 when [trace flag 2422](../database-console-commands/dbcc-traceon-trace-flags-transact-sql.md#tf2422) is enabled and the maximum CPU time is exceeded.
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#### REQUEST_MEMORY_GRANT_TIMEOUT_SEC = *value*
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‎docs/t-sql/includes/create-workload-group.md‎

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author: rwestMSFT
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ms.author: randolphwest
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ms.reviewer: dfurman
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ms.date: 09/15/2022
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ms.date: 01/13/2022
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ms.service: sql
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ms.topic: include
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---
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#### REQUEST_MAX_CPU_TIME_SEC = *value*
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Specifies the maximum amount of CPU time, in seconds, that a request can use. *value* must be 0 or a positive integer. The default setting for *value* is 0, which means unlimited.
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Specifies the maximum amount of CPU time, in seconds, that a batch request can use. *value* must be 0 or a positive integer. The default setting for *value* is 0, which means unlimited.
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By default, resource governor doesn't prevent a request from continuing if the maximum time is exceeded. However, an event is generated. For more information, see [CPU Threshold Exceeded Event Class](../../relational-databases/event-classes/cpu-threshold-exceeded-event-class.md).
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When the maximum CPU time is exceeded, the `cpu_threshold_exceeded` extended event and a trace event are generated. For more information, see [CPU Threshold Exceeded Event Class](../../relational-databases/event-classes/cpu-threshold-exceeded-event-class.md).
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Starting with [!INCLUDE [sssql16-md](../../includes/sssql16-md.md)] SP2 and [!INCLUDE [sssql17-md](../../includes/sssql17-md.md)] CU3, and using [trace flag 2422](../database-console-commands/dbcc-traceon-trace-flags-transact-sql.md#tf2422), resource governor aborts a request when the maximum CPU time is exceeded.
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In Azure SQL Managed Instance, when the maximum CPU time is exceeded, resource governor aborts the request with error 10961.
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In [!INCLUDE [ssnoversion-md](../../includes/ssnoversion-md.md)], resource governor doesn't abort the request by default. However, starting with [!INCLUDE [sssql16-md](../../includes/sssql16-md.md)] SP2 and [!INCLUDE [sssql17-md](../../includes/sssql17-md.md)] CU3, resource governor aborts a request with error 10961 when [trace flag 2422](../database-console-commands/dbcc-traceon-trace-flags-transact-sql.md#tf2422) is enabled and the maximum CPU time is exceeded.
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> [!NOTE]
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> The detection interval for CPU time usage is five seconds. An event is generated if a query exceeds the specified limit by at least five seconds. However, if a query exceeds the specified threshold by less than five seconds, its detection might be missed depending on the timing of the query and the time of last detection sweep.
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#### REQUEST_MEMORY_GRANT_TIMEOUT_SEC = *value*
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