DCCA hired BluePhoenix to translate roughly 1 million lines of Natural code into Java and convert existing IBM JCL (Job Control Language) code to Korn shell scripts, using automatic tools developed especially for this project. That translated code isn’t particularly object-oriented or well-formed, Nielsen says, but it functions well, and most importantly, it’s accessible for maintenance and fine-tuning. The new system uses the network more heavily because of increased traffic between servers and to support 3270 terminal emulation for connections to some outside systems. Nielsen, however, says this was a manageable increase.
Swapping out mainframe hardware, code, and databases at the same time introduces a lot of risk. Nielsen says a key factor in ensuring that DCCA’s transition ran smoothly was avoidance of translating and changing the code’s functionality simultaneously, as had been done in a previous, failed migration effort. Such changes would introduce too many variables, he says, making it difficult to verify that the new code was correct. By doing the translation first, the agency could rework the translated applications later, optimizing them and adding new functionality -- in the meantime it could still run its business using the translated code.
Sabre Pushes the Limits
Sabre Holdings -- parent of the Travelocity online consumer booking service and the Sabre travel reservations and ticketing system, which handles about 40 percent of worldwide travel reservations -- is in the midst of one of the largest mainframe migrations. Todd Richmond, the company’s vice president of enterprise architecture, says Sabre has the world’s third-largest implementation of IBM TPF (Transaction Processing Facility) mainframes. In an effort that began almost six years ago, however, Sabre has migrated most of its domestic booking services to four-way, Intel Itanium-based HP NonStop servers and a cluster of HP Integrity Itanium-based servers running 64-bit Red Hat Linux and the MySQL database.
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Sabre’s road away from the mainframe has not been easy, and the project is still several years from completion. This year, the company encountered unexpected problems in managing its server farms. “It’s our No. 1 challenge,” Richmond says, adding that Sabre had to build a lot of middleware to replicate the mainframe’s end-to-end monitoring and self-management capabilities. “There are more hops now, so we have to be diligent about latency.”
Sabre still experiences periods when reliability isn’t the same as it was on the mainframe, Richmond says, but it has gained the advantage of much shorter development windows -- perhaps half as long -- owing to the combination of the move away from assembly language and the use of desktop development tools. Richmond’s staff has also been able to code functions such as calendar-based flight availability in C++ and Java, which he believes could not have been done using mainframe code.