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[Catherine]

There were 2 transactions T1, T2 corresponding to a Single Program P which were trying to WRITE to the File F1
( T1 , T2 are multiple transaction running on a single program )

The Program P actually performs the following - READ is issued to the file first and then a WRITE after

T1 & T2 encountered a deadlock with each other while WRITE to the File F1

Let me know what are the options to remove this deadlock while writing to file
Will deadlock occur only while performing specific type of operations on a File? like my case READ and then WRITE?

[kolusu]

Catherine,

Since this is a CICS forum , I am assuming that you are writting to a vsam cluster. Read up on the

SHAREOPTIONS(crossregion[ crosssystem]]1 3)

Kolusu
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Kolusu
www.linkedin.com/in/kolusu

[Catherine]

Thanks Kolusu

My VSAM File is defined to have a SHARE OPTION ( 2 3)
T1 & T2 transactions belong to the same CICS region
Other SHARE OPT 3, 4 are not recommended as per our standards

This means that there can be multiple reads made by users concurrently
but for WRITE only one transaction can do it

The transaction takes an exclusive lock during the WRITE
When T1 & T2 tried to take exclusive Lock during the Write process they encountered the deadlock. Correct me if Im wrong

1) When encountering a deadlock with a VSAM File, Will not one of the transactions abend or return with a invalid CICS response?
My transactions looked to indefinitely wait for each other until we killed one of the transactions T2 after 6 minutes

2) Since Changing SHAREROPT is not possible due to standards ( 3, 4 NOT RECOMMENDED ) . Please advise