cpu-busy-transact-sql.md

title	@@CPU_BUSY (Transact-SQL) | Microsoft Docs
ms.custom
ms.date	09/18/2017
ms.prod	sql
ms.prod_service	sql-database
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ms.technology	t-sql
ms.topic	language-reference
f1_keywords	@@CPU_BUSY_TSQL @@CPU_BUSY
dev_langs	TSQL
helpviewer_keywords	CPU [SQL Server] status information [SQL Server], CPU ticks [SQL Server] time [SQL Server], CPU activity @@CPU_BUSY function statistical information [SQL Server], CPU CPU [SQL Server], activity
ms.assetid	81ae0e64-79fa-4a74-9aa5-37045c4cd211
author	MikeRayMSFT
ms.author	mikeray

@@CPU_BUSY (Transact-SQL)

[!INCLUDEtsql-appliesto-ss2008-xxxx-xxxx-xxx-md]

This function returns the amount of time that [!INCLUDEssNoVersion] has spent in active operation since its latest start. @@CPU_BUSY returns a result measured in CPU time increments, or "ticks." This value is cumulative for all CPUs, so it may exceed the actual elapsed time. To convert to microseconds, multiply by @@TIMETICKS.

Note

If the time returned in @@CPU_BUSY or @@IO_BUSY exceeds 49 days (approximately) of cumulative CPU time, you may receive an arithmetic overflow warning. In that case, the value of the @@CPU_BUSY, @@IO_BUSY and @@IDLE variables are not accurate.

Transact-SQL Syntax Conventions

Syntax

@@CPU_BUSY  

Return types

integer

Remarks

To see a report containing several [!INCLUDEssNoVersion] statistics, including CPU activity, run sp_monitor.

Examples

This example returns [!INCLUDEssNoVersion] CPU activity, as of the current date and time. The example converts one of the values to the float data type. This avoids arithmetic overflow issues when calculating a value in microseconds.

SELECT @@CPU_BUSY * CAST(@@TIMETICKS AS float) AS 'CPU microseconds',   
   GETDATE() AS 'As of' ;  

[!INCLUDEssResult]

CPU microseconds As of
---------------- -----------------------
18406250         2006-12-05 17:00:50.600

See also

sys.dm_os_sys_info (Transact-SQL)
@@IDLE (Transact-SQL)
@@IO_BUSY (Transact-SQL)
sp_monitor (Transact-SQL)
System Statistical Functions (Transact-SQL)