With IBM i 6.1 (i5/OS V6R1), IBM will require conversion of all programs created under previous releases that use the IBM i Machine Interface (MI). This conversion upgrades and refreshes programs to take advantage of the latest system enhancements, including enhanced system integrity, improved performance, and a range of new operating system and processor capabilities. In order for a program to be converted, its creation data (sometimes referred to as observability) must be available. Programs created for IBM i V5R1 or later automatically retain creation data sufficient for conversion. Clients and ISVs with programs created for OS/400® V4R5 and earlier need to ensure that creation data is available for the conversion process.
IBM has provided the Analyze Object Conversion (ANZOBJCVN) tool for IBM i 5.3 and 5.4 (i5/OS V5R3 and V5R4) to help you plan for program conversion. This tool helps you identify potential conversion difficulties, if any, and estimates the time required for program conversion.
Looking for additional information on program conversion? Checkout the ITSO Redpaper IBM i Program Conversion: Getting ready for IBM i 6.1.
Q&A — Program conversion
Q1. What does "program conversion" mean?
A1. Conversion is a general term for applying changes to objects, which has been used to describe other system changes. In this particular case, "upgrade" or "refresh" are more descriptive. Each Machine Interface program will retain its name, location, owning user profile and other such attributes. The Machine Interface operations it performs will be the same. However, the internal format of the program object will be changed, and the executable hardware instructions will be replaced.
Q2. Which releases are affected, and how?
A2. Programs will have a new format on i 6.1M0, so programs created for earlier releases will be converted before they run on i 6.1M0 or later releases. Similarly, programs created on i 6.1M0 or later releases will be converted before they run on V5R4M0 or an earlier release.
Q3. Why convert programs now?
A3. Software design and hardware used by the System i platform are now at a point where significant improvements to vital system aspects — integrity, performance and functionality — can be provided, simply by taking advantage of the system architecture to transform programs.
Q4. Has program conversion ever occurred before?
A4. This conversion is the third in the history of the Machine Interface architecture. The first occurred when moving from System/38 to AS/400 V1R1M0 in 1988. The second occurred for AS/400 V3R6M0 in 1995, when upgrading programs from 48-bit to 64-bit addresses and running a different hardware instruction set. This conversion will be simpler than previous ones. Most other types of objects are not changing this time, for example. Program conversions should also be much faster this time.
Q5. What choices do I have about when conversion occurs?
A5. Program conversion or transformation can occur in three different ways: during install or load, as explicitly scheduled, or when a program will first be run. You can freely mix and match conversion methods to best suit your own situation.
Q6. Do I need source and a compiler?
A6. No, not in most cases. The transformation of programs will be handled by System i Licensed Internal Code, with no need for a recompile. There are a few exceptions, covered in a later question and answer.
Q7. How do I know if my programs can all be converted?
A7. As included in the product preview, in general programs created for releases V5R1M0 and later can be converted. The only exceptions are those that have been altered in unsupported ways. Programs created for releases V4R5M0 and earlier can be converted unless their creation data has been completely removed. Programs that cannot be converted must be recompiled from source. IBM provides the ANZOBJCVN tool, delivered by PTF for running on V5R4M0 or V5R3M0, to assess whether programs can be converted. The tool also estimates conversion times.
Q8. How does conversion compare with binary compatibility?
A8. Binary compatibility allows programs to run without change, though potentially in a degraded fashion if the underlying hardware has changed substantially. In contrast, program conversions on the System i platform allow programs to run without change but in an upgraded manner, especially if the underlying hardware has changed substantially. The System i platform supports binary compatibility between conversions but occasionally uses conversion to improve and upgrade programs. Other commercial systems are not built on architectures that can improve software functionality through program object conversion.
Q9. Will my System/36 environment and System/38 environment programs still run?
A9. Yes. Those programs can also be converted to run on i 6.1. The only exception would be if creation data was removed for some reason. You can use ANZOBJCVN to confirm that these programs can be converted.
Q10. How can software providers ask specific questions?
A10. Contact the IBM ISV Enablement for IBM i group, at firstname.lastname@example.org. Please include your PartnerWorld number.
Q11. I am a software provider; how do I inform IBM that my application is ready to run on i 6.1?
A11. Contact the IBM ISV Enablement for IBM i group, at email@example.com. Please include your PartnerWorld number, specific product name, and version information.