REGION error

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REGION error

Post by korix » Sat Oct 04, 2008 8:18 am

I'm encountering an error if I use REGION=0M in the jobcard, so I need to change it to REGION=999M. What's the difference does it make?

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Post by dbzTHEdinosauer » Sat Oct 04, 2008 3:27 pm

try using REGION=6M. you can read in the JCL documentation what it means.
Dick Brenholtz
JCL, SQL and code in programs have an irritating habit of doing what you say,
not what you meant.

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Post by korix » Mon Oct 06, 2008 8:43 am

Thanks Dick!

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Post by Anuj Dhawan » Sun Nov 23, 2008 2:11 pm


Just for my .02 cents..

A value of 0K or 0M will allow the program to request the largest available region size, however this specification should be used with caution. From the OS/390 Initialization and Tuning Guide,

"The region size allowed to users can affect performance of the entire system. When there is no limit on region size and the system uses its default values, users might obtain so much space within a region (by repeated requests for small amounts of storage or a single request for a large amount) that no space would remain in the private area for system use. This situation is likely to occur when a program issues a request for storage and specifies a variable length with such a large maximum value that most or all of the space remaining in the private area is allocated to the request. If this program actively uses this large amount of space (to write tables, for example), it can affect central storage (also known as real storage) and thus impact performance."

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