For IBM Automatic Binary Optimizer for z/OS usage or maintenance related questions

Frequently asked questions

Choosing the right fit

What is the difference between Enterprise COBOL and IBM Automatic Binary Optimizer for z/OS?

Enterprise COBOL is an optimizing compiler that takes in program source and produces COBOL modules. IBM® Automatic Binary Optimizer for z/OS® (ABO) is a binary optimizer. It takes in COBOL load modules and produces optimized modules, while maintaining the behaviors of the original modules.

Is ABO just the optimization phase of the Enterprise COBOL 6 compiler?

No, although ABO and Enterprise COBOL 6 share the same optimization framework. ABO is the state-of-the-art technology that directly optimizes compiled load modules. No compile step is required.

Can Enterprise COBOL and ABO be used together?

Yes. You are recommended to use both Enterprise COBOL and ABO together because they complement each other. Use Enterprise COBOL for new development, modernization, and maintenance. Use ABO to improve the performance of the modules that are not frequently updated or do not have a recompilation plan. With ABO 2.2, you can future proof performance and simplify complex build environments.

How can ABO help me with COBOL migration?

Migration to COBOL 6 involves detecting, testing, and fixing issues in existing application source. You can reduce the scope by migrating code only under active development to COBOL 6 and use ABO to improve the performance of code you have not compiled in a long time.

Can ABO help me if I lost my COBOL source code?

Yes. ABO does not require source code or compiler migration. Use ABO to optimize your compiled programs that are not in your recompile plan or if the program source code is not available.

What CPU savings can you expect from code that is produced by different versions of COBOL compilers?

ABO optimized modules can show comparable performance to compiler produced modules. In general, the performance is closest to the latest COBOL compiler when ABO optimizes code from COBOL 4 or below, or from COBOL 5 or up that did not specify the most optimal set of performance options at the time of compilation.

Do ABO modules suffer from Enterprise COBOL 6 migration pitfalls like invalid data, uninitialized variables, and data item overpopulation that can happen after being recompiled?

No. ABO directly optimizes COBOL modules. ABO is not affected by any source-related issues. With ABO, you will not encounter issues such as invalid data, overpopulated data items, and parameter size mismatches. There is no need to fix the source before optimizing with ABO and deploying.

Can ABO help reduce MLC costs?

Yes, COBOL modules that are optimized by ABO consume fewer CPU resources. As a result, both MLC costs and processing time for business-critical applications can be reduced and the ROI from your Z hardware is improved.

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What are the Enterprise COBOL compiler versions eligible for ABO optimization?

ABO can optimize programs compiled from VS COBOL II 1.3 up to and including the latest Enterprise COBOL 6 compiler. You can find the full list of the eligible Enterprise COBOL compiler versions at the link below.

What are the minimum hardware requirements for running ABO?

ABO 2.2 can run on any IBM Z® system supported by z/OS V2R3 and above.  For a complete list of IBM Z servers, see the attached link.  
The optimized modules that are produced by ABO can run on z14 and later IBM Z systems.

How much is ABO be able to improve the performance of my applications?

ABO performance improvements depend on three factors:

  • Amount of time spent in COBOL code and select LE routines
  • Amount of computationally intensive COBOL code
  • IBM Z level where the application runs and ABO ARCH level setting

Use the ABO Assistant to determine improvements on COBOL applications.

What are the characteristics of the applications that will benefit the most from ABO optimization?

Applications, where a significant portion of the CPU time is spent in the COBOL code or some select LE routines, can benefit the most from ABO optimization. Applications that spend most of their time in CICS®, Db2®, IMS, or performing I/O will benefit less.

Do all modules in an application have to be optimized by ABO to see benefits?

To get the most benefit from ABO, optimize the programs that contribute to the bulk of the CPU time in an application. You do not need to optimize all modules to see benefits.

Can we limit the use of ABO to certain modules or compiled programs?

You can decide the number of modules or CSECTs within the modules selected for optimization by ABO. ABO can optimize all modules or a single module in a data set, and ABO provides options to allow you to limit processing to one or more members of a data set or one or more CSECTs within the module. 

How do we determine which modules to optimize to obtain the most performance gains and cost reductions?

The ABO Assistant simplifies an ABO performance evaluation and accelerates deployment. Starting from your provided SMF data, the ABO Assistant finds your top CPU-consuming applications and then enables you to drill down to clearly report on the CPU time savings from using ABO.

Can I see gains in my batch and online applications?

You can see CPU reductions in both batch and online applications. However, in general, batch applications tend to see larger improvements since they often have more time spent in the COBOL code as opposed to other subsystems like CICS, Db2, and IMS.

Can ABO handle calls to other programming languages?

Yes. ABO is 100% interoperable when calling or being called by other compiled levels of COBOL or other languages.

Can ABO handle all OPTIMIZE settings that are used by COBOL to generate the original load module?

ABO can effectively optimize modules regardless of the original compiler OPTIMIZE setting.


What are the trial options for this product?

ABO offers two 90-day no-charge trials. You can get started immediately with the Trial Cloud service. No installation is required. Sign in and upload COBOL modules to be optimized. You can order the on-premises trial in Shopz. It comes with the ABO assistant that is designed to speed up evaluation.

How do I obtain ABO and the ABO trial?

You can order ABO and the ABO on-premises trial via Shopz or by contacting your IBM representative to place the order for you. The following technote provides a step-by-step guide for ordering the two editions from Shopz.


How can I find out what is new with ABO?

You can find what's new in an ABO release and continuous delivery (CD) PTFs at the following link.   

How often are updates available for ABO?

ABO is released on a continuous delivery cycle. See how frequently IBM is releasing updates at the following link.

How do I obtain ABO PTFs?

You can order ABO PTFs via Shopz or by contacting your IBM representative to place the order for you. The following technote provides a step-by-step guide for ordering ABO PTFs from Shopz.

How do I find needed information when I report ABO problems?

Refer to the instructions at the following link to prepare the information that is required for opening your support case with IBM.

How can I request an enhancement to ABO?

Use Request for Enhancement (RFE) Community to collaborate directly with the IBM product development teams and other users.