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Difference between -911 and -904 in DB2


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Narismha

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Joined: 22 Nov 2006
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Location: Mumbai

PostPosted: Fri Dec 08, 2006 1:00 pm
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Hi,

-911 is for deadlock or timedout. -904 is for resource not available.

As per my understanding when we get -911 , we have to wait for some time and after that we restart that job with proper restart instructions. Even for -904 also we do the same thing. So for both cases our conclusion is RESOURCE NOT AVAILABLE.

Deadlock example is PGM1 holding Resource R1 and waiting for resource R2 and PGM2 holding R2 and waiting for R1.

Please explain me why do we get -911 ? (If its also for resource not available problem then why don't we get -904?). From the above example Is it possible to abend the both PGM1 and PGM2 ??
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cobolunni

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Joined: 07 Aug 2006
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PostPosted: Fri Dec 08, 2006 2:50 pm
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-904 is unsuccessful execution caused by unavailable resource
and -911 is current unit of work has been roll backed by dead lock or time out
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cobolunni

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PostPosted: Fri Dec 08, 2006 2:54 pm
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hello see this attachment for more info
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Narismha

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Joined: 22 Nov 2006
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PostPosted: Mon Dec 11, 2006 2:03 pm
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Hi Cobolunni,

Thanks for your document.

"As per my understanding when we get -911 , we have to wait for some time and after that we restart that job with proper restart instructions. Even for -904 also we do the same thing. So for both cases our conclusion is RESOURCE NOT AVAILABLE.
If both are for resource not available problems then why don't we get -904 instead of -911?. "

Please let me know if my question is not clear.

Regards,
Narisimha
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cobolunni

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PostPosted: Mon Dec 11, 2006 6:19 pm
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hello narismha,
Actually -904 atands for unavailable resource and we will not be able to do any data base function such as insert update etc in that case. And -911 stands for current unit of work has been roll backed because
of timeout or dead lock .In case of -911 we had done several functions on data base such as insert update etc and while doing these seres of function one function caused dead lock or timeout occurred ( Remember we had several data base functions to be committed) then all the seres of updations done on data base will be rollback and thus we will lose all the data that we updated. Actually -911 is not the case of resource unavailable its the case rollback done, also dead lock is not actually the case of resource unavailable
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William Thompson

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Joined: 18 Nov 2006
Posts: 3156
Location: Tucson AZ

PostPosted: Mon Dec 11, 2006 6:37 pm
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Narismha wrote:
If both are for resource not available problems then why don't we get -904 instead of -911?

Different types of resources.
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cobolunni

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PostPosted: Mon Dec 11, 2006 7:31 pm
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There are many resource types such as data base,table space,index space,compression dictionary,page,security server,table space page,storage group etc.These different types of resources creates both -904 and -911
but the effect of these are different
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MFRASHEED

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Joined: 14 Jun 2005
Posts: 186
Location: USA

PostPosted: Mon Dec 11, 2006 9:14 pm
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With -911 DB2 will issue a rollback and application has no control what so ever, so application will loose all data until last commit. Deadlock or resource un-available is of a serious nature.

With -904 , application could be in a deadlock (contention) and application has control, application can have a re-try logic and try again.
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