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VSAM Massinsert Write & locking

 
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deepa12
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PostPosted: Wed Feb 25, 2015 12:50 am    Post subject: VSAM Massinsert Write & locking Reply with quote

With respect to the following link:
http://www-01.ibm.com/support/knowledgecenter/SSGMCP_5.2.0/com.ibm.cics.ts.applicationprogramming.doc/topics/dfhp3a9.html

where
The empty range is locked to stop other requests simultaneously adding records into it. Moreover, the record defining the end of the empty range cannot be removed during the add operation. If another transaction issues a request to add records into the empty range or to delete the record at the end of the range, the delete lock makes the transaction wait until the WRITE or WRITE MASSINSERT command is complete. The record held with a delete lock can, however, be updated by another transaction during the write operation if it is in another CI.

With respect to this:
I was suggested to use mass insert option since there can be say 100000 records. This file is a recording mechanism for incoming & outgoing messages (mainframe to non mainframe) For some messages the key values i.e 56 are a combination of alpha numeric & numeric. For the message am taking about it is ending with numeric

There is SYNCPOINT after every 3500 records

I think CI range lock will also be against the index sets, sequence sets of the INDEX component.

I am not sure whether while the MASSINSERT transaction is running some other transaction could also try to acquire the same CI Please let me know how to find this. Also is it that based on the key values that the 2 transactions could contend for same CI

Kindly pardon me if am requesting information without enough investigation
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kolusu
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PostPosted: Wed Feb 25, 2015 1:56 pm    Post subject: Reply with quote

deepa12

Are you opening the VSAM file in RLS mode or non-RLS mode? For MASSINSERT operations on a file opened in RLS access mode, CICS acquires a separate update lock at the time each individual WRITE command is issued.

Kolusu
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deepa12
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Location: chennai

PostPosted: Wed Feb 25, 2015 11:32 pm    Post subject: Reply with quote

The file will be opened in NON RLS Mode
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