@@CPU_BUSY

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@@CPU_BUSY

VM-723206

SSCrazy

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April 16, 2009 at 9:19 pm

#208516

Comments posted to this topic are about the item @@CPU_BUSY

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ichacmoll Mr or Mrs. 500 Points: 554 More actions · Answer 1

I disagree with the answer, that the return value exceeds the limit of an integer, a variable of type integer is not able to save millions

Steve Jones - SSC Editor SSC Guru Points: 736212 More actions · Answer 2

Really? AFAIK an integer hold a few billion:

http://msdn.microsoft.com/en-us/library/aa933198(SQL.80).aspx

TheRedneckDBA SSChampion Points: 14001 More actions · Answer 3

ChacMoll (4/17/2009)
I disagree with the answer, that the return value exceeds the limit of an integer, a variable of type integer is not able to save millions

The answer is correct.

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

The Redneck DBA

Chad Crawford SSChampion Points: 11610 More actions · Answer 4

Jason Shadonix (4/17/2009)
ChacMoll (4/17/2009)
I disagree with the answer, that the return value exceeds the limit of an integer, a variable of type integer is not able to save millions
The answer is correct.
Per books online: If the time returned in @@CPU_BUSY or @@IO_BUSY exceeds approximately 49 days of cumulative CPU time, you receive an arithmetic overflow warning. In that case, the value of @@CPU_BUSY, @@IO_BUSY and @@IDLE variables are not accurate.

Have that happen to me all the time. I wrote some monitoring scripts that aggregate and graph CPU usage on a regular basis and it dies after the server has been up for a long time. Guess I should be happy it doesn't require a reboot that often!

ichacmoll Mr or Mrs. 500 Points: 554 More actions · Answer 5

Sorry, my comment was too hasty, because I answer the question the wrong way.

I totally agree my mistake.

Steve Jones - SSC Editor SSC Guru Points: 736212 More actions · Answer 6

No worries. The questions aren't here to mark you with a score. They're here to get you to think about things, and perhaps learn something.

And they teach me how to better ask questions. Believe me, I'm sure I make more mistakes asking them than you do answering!

ashishandgod Newbie Points: 5 More actions · Answer 7

Returns the time that SQL Server has spent working since it was last started. Result is in CPU time increments, or "ticks," and is cumulative for all CPUs, so it may exceed the actual elapsed time. Multiply by @@TIMETICKS to convert to microseconds.

select @@CPU_BUSY,@@TIMETICKS ,@@CPU_BUSY*@@TIMETICKS

SanjayAttray SSChampion Points: 13157 More actions · Answer 8

Jason Shadonix (4/17/2009)
ChacMoll (4/17/2009)
I disagree with the answer, that the return value exceeds the limit of an integer, a variable of type integer is not able to save millions
The answer is correct.
Per books online: If the time returned in @@CPU_BUSY or @@IO_BUSY exceeds approximately 49 days of cumulative CPU time, you receive an arithmetic overflow warning. In that case, the value of @@CPU_BUSY, @@IO_BUSY and @@IDLE variables are not accurate.

I think for @@CPU_BUSY it should be for 24 and 3/4 days, if counted in Milliseconds.

Int can take value upto 2,147,483,647

and 24*60*60*1000 = 86400000

SQL DBA.