The proud owners of the biggest and strongest HP 3000s in the community are the ones most eager for the 6.5 release of MPE/iX, and HBOC officials can’t wait to get their customers on the new operating system. But ordering an upgrade to 6.5 less than six weeks after the operating system shipped was just too quick for some sites. Tooled for the demanding requirements of organizations managing databases for hundreds of thousands of subscribers, 6.5 was being positioned as a mandatory MPE release by HBOC during March. Customers reported receiving letters that they had to be moved over to 6.5 by May to remain on support, a blistering migration pace for shops that can experience virtually zero downtime and run 3000s that take the longest to move to a new OS version.

HBOC reportedly had second thoughts about the schedule when technicians were reminded of the differences between 6.0 and 6.5 COBOL compilers on the HP e3000. Programs and applications compiled for 6.5 may not execute under MPE/iX 6.0 because of changes to millicode. The compiler was updated in 6.5 to generate code that takes advantage of new 64-bit millicode routines. If Amisys becomes a 6.5-or-else proposition, customers staying on 6.0 wouldn’t have access to changes compiled for the 6.5 MPE/iX release. HP’s latest Communicator article on the release’s compiler changes says that “if you compile a COBOL II/iX program on an MPE/iX 6.5 system and try to link it on a pre-6.5 system, you may have unresolved externals because of calls to the new millicode routines. These unresolved externals might be reported at link time, but it is possible that the problem would not show up until load time, with unrelated errors reported by the RUN command. The recommended procedure is to link on the 6.5 system, where the latest millicode library is available.” HP has always guaranteed forward compatibility for programs, but rarely promises backward compatibility. Old code should run forever on e3000s, but new compiles stand a good chance of only running on new releases.