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An additional benefit of the OS / 390 packaging concept was to improve reliability, availability and serviceability ( RAS ) for the operating system, as the number of different combinations of elements that a customer could order and run was drastically reduced.

This reduced the overall time required for customers to test and deploy the operating system in their environments, as well as reducing the number of customer reported problems ( PMRs ), errors ( APARs ) and fixes ( PTFs ) arising from the variances in element levels.