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william51
Warnings : 1
New User
Joined: 06 Jul 2006
Posts: 31
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I got a job JOBA which has 3 steps. File FILEA is used in the 3rd step with exclusion mode(OLD).
When the second step in JOBA is in processing, can another job JOBB use file FILEA at the same time?
Thanks. |
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Dsingh29
Active User
Joined: 16 Dec 2008
Posts: 132
Location: IBM
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i think it depends on the JES system you are using....JES2 and JES3 have different methodology about dataset allocation. You can google more about their difference.
Suggestions welcome !! |
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gcicchet
Senior Member
Joined: 28 Jul 2006
Posts: 1702
Location: Australia
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Hi,
it shouldn't be too difficult to test it out.
Gerry |
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Jeffrey Ranney
New User
Joined: 23 Dec 2010
Posts: 20
Location: USA
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| The answer is *NO*... JCL will have exclusive use of that file while the job is running. |
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mlp
New User
Joined: 23 Sep 2005
Posts: 91
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This is from JCL reference.
If a dynamic allocation requests exclusive control of a data set then all subsequent DISP=SHR JCL references to that data set within that job will be upgraded to exclusive control. The job will retain exclusive control of that data set until the end of the last step of that job which references that data set in its JCL.
| Code: |
//STEP1 EXEC PGM=anypgm1
//DD1 DD DSN=A.B.C,DISP=SHR
//STEP2 EXEC PGM=IDCAMS
DELETE A.B.C DEFINE A.B.C
//STEP3 EXEC PGM=anypgm3
//DD3 DD DSN=A.B.C,DISP=SHR
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Before the start of STEP1, the job will request shared control of data set A.B.C. In STEP2, the DELETE/DEFINE of data set A.B.C will cause the shared control from STEP1 to be upgraded to exclusive control. In STEP3, control of data set A.B.C will remain exclusive, since it is not possible to downgrade an ENQ from EXCL to SHR.
For rest of the dispositions (MOD,OLD,NEW) there will be excusive lock on the dataset.
For further details refer the JCL reference. |
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william51
Warnings : 1
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Joined: 06 Jul 2006
Posts: 31
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| Thank you all for your kindly reply! |
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