White Paper              Migration to zTPF
IntroductionThis white paper presents an approach towards migration of TPF 4.1 system to z/TPF system. Itsummarizes some o...
A Migration Plan:This plan is going to list the key action items, which should identify and document all the hardware ands...
• Test using teleprocessing network simulator (TPNS).        • Test offline.        • Test operations, including any autom...
Appendix ATPF Assembler:A total of 524 TPF assembler programs containing 324309 lines of code - resulted in 2864errors whe...
InterGlobe Technologies (IGT) is a leading BPO & IT Services provider committed todelivering innovation and business excel...
Upcoming SlideShare
Loading in …5
×

Migration to z/TPF

5,899 views

Published on

This white paper presents an approach towards
migration of TPF 4.1 system to z/TPF system. It
summarizes some of the benefits of a z/TPF system
over TPF 4.1 system and primarily describes
important considerations to do this migration.

Published in: Technology
1 Comment
3 Likes
Statistics
Notes
No Downloads
Views
Total views
5,899
On SlideShare
0
From Embeds
0
Number of Embeds
24
Actions
Shares
0
Downloads
39
Comments
1
Likes
3
Embeds 0
No embeds

No notes for slide

Migration to z/TPF

  1. 1. White Paper Migration to zTPF
  2. 2. IntroductionThis white paper presents an approach towards migration of TPF 4.1 system to z/TPF system. Itsummarizes some of the benefits of a z/TPF system over TPF 4.1 system and primarily describesimportant considerations to do this migration.What is z/TPF?z/Transaction Processing Facility system is a high-performance operating system that runs on andexploits IBMs zSeries servers, an infrastructure offering transaction processing with high qualityservice demands.Following are some of the benefits of a z/TPF system over TPF 4.1 system: • Use of 64-bit z/Architecture with 64-bit real addresses and 64-bit virtual addresses which enables large-scale memory blocks and applications thereby resulting in better efficiency. • Open systems architecture – Linux based build environment and GNU compiler collection allows z/TPF to share applications, tooling, and development infrastructure with the most common open system available, Linux. • Constraint Relief • Has the ability to use more than 2 GB of real storage. • Support for as many as 255 subsystem users (SSUs). • Can support upto 40 000 DASDs • Support for as many as XFFFF symbolic device addresses (SDAs), including tape addresses. • Coexistence - with the High Performance Option (HPO) feature, TPF 4.1 system and z/TPF system can run under the same complex and it is also possible to use single set of source for applications that need to run on both the TPF 4.1 and z/TPF systems.Migrating from TPF 4.1 to z/TPFMigration to z/TPF involves several tasks right from careful planning to rigorous testing of the completesolution before actual implementation. Migration is not just porting of applications to a different platformbut instead, it requires robust & extensive project planning ensuring successful final implementation.Expertise - not just in the area of system integration will be required but ‘technical’ and ‘functional’experience is required to keep the business logic intact and ensure a smooth business transition.Since z/TPF is based on the open-systems architecture, which presumably enables more efficient useof applications, some processing techniques, will need to be eliminated and code optimization will berequired. Largely this would be taken care by IBM’s TPF Tool kit, however a great portion depend onthe expertise of the migration team.One thing we need to remember is that, this is not just going to be migration as z/TPF migrationinvolves migration of large systems to new open system platforms, rigorous testing will be the key tosuccessful implementation.Listed below are some of the activities, tools and techniques suggested and provided by ‘IBM’ toachieve this migration, at least up to a level where the code has been optimized enough to be calledz/TPF compliant or in other words single source code. © InterGlobe Technologies Ltd. 2011: www.igt.in
  3. 3. A Migration Plan:This plan is going to list the key action items, which should identify and document all the hardware andsoftware needed for this migration. This may be IBM or Non-IBM.1) Sound Documentation, good documentation of the existing environment should list all the hardware,software tools that are currently used. Hardware/software that is currently used but will no longer besupported the new system, followed by identification of the following requirements as well.2) Requirement Understanding: • Any new hardware and software requirements. • Network requirements or any changes to the existing network that may be essential. • New or changed data set requirements. • What are the main storage requirements. • To ensure that the z/TPF system has enough DASD space, it’s good to identify any new records, changes required to existing records, and records that are no longer supported.3) Training will play a very important role in the implementation. With the new system in place varioususers will need to be identified.Some of those key personnel’s will be: • Coverage programmers • System programmers • Application programmers • Automation personnel • Operators • Planning personnel • System support personnel4) Interface modification such as changes to commands and messages that will affect the automationprocedures may be required. Additional identification of changes to macros and C or C++ functionsthat will affect the system and application programs is essential.5) Environment Preparation, Finally a good to do activity would be - preparing the environment formigration. This basically is the identification the migration tasks that can be done to the existing TPF4.1 system and TPFDF 1.1.3 product before receiving the z/TPF system and z/TPFDF productA Fallback Plan:Planning for a fallback is as important as looking forward to a successful implementation. Whathappens if you decide to rollback to TPF 4.1? Will it be just about simply switching the traffic back to4.1 or something more than that?A rollback process to revert to TPF4.1 environment therefore needs to be in place.Developing a Test Strategy:Testing is the key to success. The test strategy, this should have following considerations: • Preparation of various test plans such as, integration, system and regression test plan. • Test high-exposure operations. • Test tools (IBM and non-IBM). • Test application programs. © InterGlobe Technologies Ltd. 2011: www.igt.in
  4. 4. • Test using teleprocessing network simulator (TPNS). • Test offline. • Test operations, including any automation packages that may have been installed. Use the online operations staff to test before the migration. • Test the utilities (capture and restore, recoup, online load, data collection, and so on). • Perform a system test. • Perform a regression test. • Test communications. • Test the inter-node communications. • Test the network. • Determine the impact of testing ongoing migration plans.Migration Tools:IBM TPF Toolkit for WebSphere Studio provides tools to convert the application source code from TPF4.1 system to single source for z/TPF system. The TPF Toolkit tools can scan both assembler and Clanguage source and identify problems that would prevent the user from having single source code.These tools are capable of detecting migration issues and can also fix them automatically. Thishappens when the tool has detected a problem with 100% accuracy. In some cases the tool can detectmigration issues but the errors cannot be fixed automatically; manual fix is required in these cases.And there might also be other conditions that need be checked manually before it can be determined ifthe problem is a single source error or not, these may not be detected by the tool at all.Migration Technique:The migration technique basically involves the process of converting application source code to singlesource code and then maintaining this code until the migration to z/TPF is complete.Below is the process in brief for converting the application code to single source code.Converting The Application to Single SourceBy single source we mean code that currently runs on TPF 4.1 that has been updated and optimizedso as to be able to run on z/TPF as well. This allows the user to only have one copy of the applicationsource code that can be deployed on both TPF 4.1 and z/TPF.Converting a TPF application to be single source compatible involves rules to detect changes thatneed to be made to the code in order to be single source compatible. The migration scan of TPF toolkit uses such rules to detect changes that need to be made to the application code. A separate set ofrules exists for scanning the Assembler Language code or C/C++ code.Identifying & Fixing ErrorsSome of the problems that are flagged by rules can be fixed automatically by using the single sourcetools; other problems require manual code changes. But there will still be changes, which will not bedetected by single source tools. Such changes need to identified and fixed manually.Maintaining The CodeOnce the TPF4.1 source code is converted to single source, it is important to ensure that no newerrors are introduced into the single source code, before it is migrated to z/TPF. © InterGlobe Technologies Ltd. 2011: www.igt.in
  5. 5. Appendix ATPF Assembler:A total of 524 TPF assembler programs containing 324309 lines of code - resulted in 2864errors when they were converted to single source code, using IBM’s TPF Tool kit forWebSphere Studio. This comes out to be an error percentage of 0.88%.These are some of the error categories for TPF Assembler code: • Cannot use re-locatable ADCON • Wrap macro call with DEFBC if moved • Line one must contain an instruction • IDSPAT cannot be used to get transfer vector information • IDSPNL does not exist on z/TPF • CE1S07 is obsolete on z/TPF • Decimal data type is not supported by GCC compiler • CE1RDA is obsolete on Z/TPF • CE1RDA moved from page 1 to 3 on Z/TPFTPFC:A similar exercise for TPFC shows that, for 75 programs having 104276 lines of codes resultedin 964 errors, which comes out to be an error percentage of 0.92%.These are some of the errors encountered for TPFC code: • Do not rely on 4-byte pointer size when performing calculations • Cast variables to int because long changed to 8 bytes on z/TPF • PACKED option should be surrounded with #ifdef __370__ • Cast variables to int because long changed to 8 bytes on z/TPF • Do not rely on 4-byte pointer size when performing calculations • TPF-unique header files moved to /include/tpf • Header file names must be changed to use _ instead of $ • Decimal data type is not supported by GCC compilerC++:For C++ 39 programs with 39000 lines of code gave 597 errors, which is an error percentage1.5%.These are some of the errors encountered for C++ code: • Do not rely on 4-byte pointer size when performing calculations. • Include statements with quotes may not be standard on z/TPF. • Declare variables as int because long changed to 8 bytes on z/TPF. • Cast variables to int because long changed to 8 bytes on z/TPF. • “Reset" parameter recognized by IBM compiler only. • “Packed" parameter recognized by IBM compiler only. • All pointers on z/TPF are 64bit. Change to 32-bit if used by assembler DSECT or mapping data in a database/file.References:The information has been referenced from: IBM TPF Product Information Center(http://publib.boulder.ibm.com/infocenter/tpfhelp) and IBM TPF Toolkit for WebSphere Studio © InterGlobe Technologies Ltd. 2011: www.igt.in
  6. 6. InterGlobe Technologies (IGT) is a leading BPO & IT Services provider committed todelivering innovation and business excellence across the entire spectrum of the travel,transportation and hospitality domain.Ranked amongst the World’s Top 3 Travel Technology Solutions providers, thecompany offers integrated Application Development and Maintenance, Call CenterServices, Back Office Services, Consulting Services and Solution Frameworks to thetravel industry worldwide. InterGlobe Technologies Pvt. Ltd. InfoTech Centre, 2nd Floor 14/2, Old Delhi-Gurgaon Road Dundahera, Gurgaon – 122016 Haryana, India T +91 (0)124 458 7000 F +91 (0)124 458 7198 www.igt.in © InterGlobe Technologies Ltd. 2011: www.igt.in

×