IBM OS/390 User Manual
32.2.2 Mass Conversion Overview / Benefits
Mass conversion is the major distinction of the CORTEX-MS process. It results in
a single switchover of the entire VSE application portfolio to OS/390 over a
weekend. Until the switchover weekend, all converted applications run in
production under VSE. By the end of the switchover weekend, all converted
applications run in production under OS/390. In the mass conversion, there is no
overlap of VSE and OS/390 production.
a single switchover of the entire VSE application portfolio to OS/390 over a
weekend. Until the switchover weekend, all converted applications run in
production under VSE. By the end of the switchover weekend, all converted
applications run in production under OS/390. In the mass conversion, there is no
overlap of VSE and OS/390 production.
Cortex MS simplifies migration by automating the conversion of programs and
JCL, and the transfer of files from VSE to MVS. It recognizes the differences
between VSE and MVS and builds an MVS version of the VSE material.
JCL, and the transfer of files from VSE to MVS. It recognizes the differences
between VSE and MVS and builds an MVS version of the VSE material.
In the mass conversion, all applications items are converted together, one
conversion step at a time. It is the opposite of a traditional progressive
conversion, in which all conversion steps are applied to the same application
item, one item at a time.
conversion step at a time. It is the opposite of a traditional progressive
conversion, in which all conversion steps are applied to the same application
item, one item at a time.
For example, in an item-by-item conversion, each program would go individually
through the successive steps of inventory, conversion, compilation/link-edit and
regression testing. Instead, in a mass conversion, the entire code inventory (all
programs, sub-programs, macros, copybooks, and include books) will first be
verified for consistency and completeness. Then it will be converted together in
one step, compiled/link-edited together in another step, and finally regression
tested.
through the successive steps of inventory, conversion, compilation/link-edit and
regression testing. Instead, in a mass conversion, the entire code inventory (all
programs, sub-programs, macros, copybooks, and include books) will first be
verified for consistency and completeness. Then it will be converted together in
one step, compiled/link-edited together in another step, and finally regression
tested.
After each mass conversion step, results are reviewed and validated not just one
at a time, but hundreds or thousands of application items at a time. Result
validation too, is performed in mass, using summary statistics to classify all
messages by occurrence and by severity. Individual manual verifications are
conducted on a sample of items that have the same message, to identify by
sampling the cause of the message and decide on a global resolution.
at a time, but hundreds or thousands of application items at a time. Result
validation too, is performed in mass, using summary statistics to classify all
messages by occurrence and by severity. Individual manual verifications are
conducted on a sample of items that have the same message, to identify by
sampling the cause of the message and decide on a global resolution.
The first mass conversion is a pilot conversion. It is used for analysis, rather
than for obtaining MVS material. The following mass conversions will be trial
mass conversions, which will deliver MVS test material with an increasing
quality, as the project and CORTEX-MS custom modification progress. Batch and
online may be converted together or separately, as both will progress at a
different pace. The final and actual mass conversion will be started after MVS
tests have been successfully completed. It will deliver the actual MVS production
material. The actual JCL conversion may be scheduled one or two weeks before
the actual program conversion, in order to apply final manual JCL modifications.
There will also be a special one-time translation of all application development
source code, but without any compilation or JCL generation. Every three to four
weeks, the mass conversion will start from a fresh copy of the entire conversion
inventory, in order to take into account the last VSE maintenance modifications.
Between two supplies, additional mass conversions may be executed from the
same supply, in whole or in part, in order to take advantage of the latest custom
modification improvements.
than for obtaining MVS material. The following mass conversions will be trial
mass conversions, which will deliver MVS test material with an increasing
quality, as the project and CORTEX-MS custom modification progress. Batch and
online may be converted together or separately, as both will progress at a
different pace. The final and actual mass conversion will be started after MVS
tests have been successfully completed. It will deliver the actual MVS production
material. The actual JCL conversion may be scheduled one or two weeks before
the actual program conversion, in order to apply final manual JCL modifications.
There will also be a special one-time translation of all application development
source code, but without any compilation or JCL generation. Every three to four
weeks, the mass conversion will start from a fresh copy of the entire conversion
inventory, in order to take into account the last VSE maintenance modifications.
Between two supplies, additional mass conversions may be executed from the
same supply, in whole or in part, in order to take advantage of the latest custom
modification improvements.
Key elements of the Cortex-MS mass conversion methodology are:
1. Automated Conversion
2. Repetitive Conversion
3. Mass Conversion (Switchover)
2. Repetitive Conversion
3. Mass Conversion (Switchover)
Chapter 32. Conversion Process
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