Core modernization: technical efficiency, financial control, and strategic vision

The mainframe continues to be a central component for industries such as banking, insurance, telecommunications, logistics, and retail, among others. 

Its stability, performance, and security make it a reliable platform for mission-critical processes. However, Its permanence should not be confused with immobility. 

Even less so when business models evolve rapidly and transactional levels increase. In this scenario, technology areas are under pressure to reduce TCO (Total Cost of Ownership), accelerate the time-to-market and align infrastructures with the principles of scalability and agility. 

That is why Core modernization becomes a survival and growth strategy.

In this article, we analyze 7 keys to approaching it in an intelligent, technical way that has a business impact.

How do companies perceive core modernization?

The report Kyndryl 2023 State of Mainframe Modernization Survey Report, revealed through the responses of the main users of this technology worldwide, that Mainframes remain essential to business operations. This was considered by the 90% of those who received the consultation..

Their robust architecture and ability to run various operating systems and applications make them extremely versatile and suitable for the banking and insurance sectors. 

Mainframes are valued by users for their levels of security (68%), reliability (60%) and performance (55%).

In fact, the The mainframe world is made up of 92% of the major banks Commercials. Their importance is such that you wouldn't be able to view your bank balance on your cell phone or process a credit card purchase without a mainframe behind them.

That's why 67% organizations are moving forward with modernizing their mainframes to optimize their performance and capacity, and to streamline their software. 

7 keys to core modernization

Faced with increasing MIPS consumption, dependence on legacy code, and pressure to integrate new architectures, It is key to rethink how resources are managed and optimized. 

This guide presents seven key elements for approaching this transformation in an intelligent, technical, and business-impacting manner. From in-depth code reviews to tuning automation and consumption governance. 

Core modernization doesn't just involve a technological upgrade. It also involves building a platform that's ready to evolve.

1. Reviewing and optimizing legacy code: the technical basis for savings

Legacy code is, in many cases, the main source of MIPS inefficiency. Why? For at least four reasons:

• Poor modularization: blocks of thousands of lines, without logical separation.
• Logical redundancy: duplicate routines, unnecessary conditions or repetitive calculations.
• Unoptimized SQL queries: Unnecessary joins, missing indexes.
• Lack of use of modern resources: Routines that could run in zIIP or distributed environments remain on the main CPU.

Code auditing should be approached with automated tools combined with expert analysis. 

But optimizing doesn't just mean refactoring. It also involves:

• Detect dead code.
• Reduce execution paths.
• Modularize for granular testing and tuning. 
• Re-evaluate the implemented business logic.

2. Precise consumption measurement: visibility for timely intervention

Mainframe costs are closely related to consumption, so it's very important to have transactions and processes running efficiently as part of core modernization.

In fact, one Much of the budget in mainframe environments is consumed by MIPS-based licensesHowever, many organizations do not know precisely which component consumes each resource.

Therefore, it is essential to establish an observability ecosystem that:

• Trace CPU usage at the job, task, transaction, and user levels.
• Distinguish between planned consumption and deviations (e.g. unjustified peaks).
• Generate dashboards with historical comparisons and projections.
• Integrate with business rules to link consumption with delivered value.

Additionally, KPIs such as cost per transaction, consumption per functional unit, or efficiency per release can be established. This allows us to move from a technical perspective to a financial view of mainframe usage.

It is also extremely important to know and detect where the problems or bottlenecks are, whether due to a poorly compiled, poorly programmed, or poorly planned process.

Even more so considering that the processes can have a Reduction of at least 20 % to 30 % in terms of usage times.

It is also essential to determine the best way to optimize performance and Increase mainframe availability by improving CICS configuration, carrying out two types of evaluations: 

• CICS Assessment configuration: A process performed to evaluate the state of the CICS configuration.
• CICS Transactional Assessment: a process performed to evaluate the performance of CICS transactions on a mainframe.

3. Batch Process Optimization: Design for Efficiency

Batch processes are ideal candidates for optimization. Poor design can create bottlenecks, fill windows, or trigger unnecessary consumption.

Key strategies to consider include:

• Smart rescheduling: reorganize execution according to the actual load and business priorities.
• Parallel partitioning: split large sequential processes into concurrent threads.
• Distributed pre-processing: filtering and transforming data in cheaper pre-mainframe environments.
• Using optimized sort and copy: Tools like Syncsort allow automatic offloading to zIIP.

A modern view suggests rethinking the very concept of batch and asking: 

• Which processes can be switched to continuous execution? 
• Which parts of processing can be turned into asynchronous events?

4. Offloading: moving what doesn't need to be on the mainframe

MIPS consumption can be radically reduced by shifting the load to:

• zIIP/zAAP: Leverage dedicated engines for DB2, Java, XML, encryption, and specific workloads.
• Distributed servers: move non-critical analysis, report generation or validations.
• Hybrid Cloud: Extract non-transactional functionalities (monitoring, integration, analytics) and process them on more cost-effective platforms.

Well-planned offloading requires identifying processes, adapting interfaces, and ensuring consistency. 

In addition, it opens the path towards decoupled architectures and microservices, which facilitates gradual migration in response to the need for core modernization.

5. Tuning automation: continuous efficiency without operational overhead

In traditional mainframe ecosystems, tuning is manual, reactive and reporting to senior specialists. Which compromises scalability.

Today It is possible to incorporate rules-based automation and artificial intelligence, which allows:

• Dynamically adjust buffers, memory pools, and job priority.
• Detect performance deviations and propose alternative configurations.
• Learn usage patterns and anticipate future behaviors.

This layer of intelligence helps reduce operational workload, avoid bottlenecks, and maintain efficiency, even with changing environments or rotating equipment. A significant achievement for core modernization.

6. MIPS Consumption Governance

Resource management should not be limited to the technical area. It requires a MIPS consumption governance that crosses business, IT and finance areas, and is based on:

• Budget policies and limits by business unit.
• A transparent and shared cost model.
• Automated alerts and reports with actionable insights.
• A cross-accountability model: where each unit knows its impact and can plan accordingly.

This approach allows us to replace the discussion of why the mainframe bill rose with an analysis of how to make the operating model more efficient.

7. Modernization as a long-term strategy: the core as an evolutionary platform

The core modernization It's not limited to a single intervention. It should be designed as a strategy for continuous core development that:

• Integrate progressive refactoring with feature encapsulation.
• Enable APIs to expose capabilities without touching the logic.
• Add DevOps practices (testing automation, adapted CI/CD).
• Promote a bimodal team: keeping the critical and developing the new.

Conclusion: efficiency, visibility and control for a sustainable future

Modernizing the core doesn't mean abandoning what works. On the contrary, it seeks to transform it so that it remains a competitive advantage instead of a technical and economic burden.

The benefits are concrete: 

• MIPS reduction.
• Lower operating costs.
• Better governance.
• Greater agility for new products.
• Architectures better prepared to integrate cloud, AI, and advanced analytics.

A comprehensive core modernization strategy requires technical investment, leadership in the change process, and a long-term vision. 

But the results in resilience, efficiency and alignment with the business justify each step of the process.

Get to know our Mainframe Center of Excellence, with which we are transforming the mainframe for the future.