IT Management

The IBM System z Integrated Information Processor (zIIP) and System z Application Assist Processor (zAAP) are designed to lower the total cost of mainframe computing by offloading the processing for many different types of applications, including Service-Oriented Architecture (SOA), Business Intelligence (BI), Enterprise Resource Planning (ERP), Java, XML, Customer Relationship Management (CRM), and select network encryption workloads.

By using specialty engines and reserving the main processing power of the mainframe for the most intensive processor duties, more work can be processed at less cost, and a mainframe upgrade or replacement can be either extended or avoided. zIIP and zAAP specialty engines provide scalability and high reliability and availability that equate to the Qualities of Service (QoS) characteristic of the IBM mainframe platform. The result for companies is more processing power with a lower Total Cost of Ownership (TCO).

zIIP Functions

The zIIP supplements the general-purpose processing MIPS with separate and less expensive zIIP MIPS. The zIIP is designed to handle processing of certain types of applications, freeing the expensive general-purpose processor for other, more intensive duties. Offloading processing onto one or more specialty engines shows immediate benefit for the System z platform in both computing capacity and cost savings.

A wide variety of software and partners support the use of zIIPs. IBM’s DB2 V8 and DB2 9 for z/OS exploit zIIP for portions of eligible workloads. For encryption processing, the z/OS Communications Server can use the zIIP for eligible Internet Protocol Security (IPsec) network encryption workloads. Eligible XML workloads can take advantage of the zIIP when z/OS XML system services are enabled. z/OS Global Mirror processing is zIIP-eligible. z/OS Communications Server employs the zIIP for the hypersocket’s large message traffic. IBM Global Business Services can enable the Scalable Architecture for Financial Reporting (SAFR) enterprise business intelligence reporting solution for zIIP. The zIIP’s execution environment accepts eligible work from z/OS, which manages and directs the work between the general-purpose processor and zIIP. IBM partners also provide a wide range of supporting solutions. 

The zIIP enables data to be centralized on the mainframe. The ease and economy of this solution makes transactional data stores on the mainframe accessible to and from BI, ERP, and CRM applications that run on distributed computers. The zIIP helps protect the data and transactions that originate from the mainframe; on the System z9 and System z10, zIIPs help minimize the need to maintain duplicate copies of data. The zIIP also provides security between the applications and the data, keeps data stores resilient, and improves resource optimization.

IBM doesn’t currently impose software charges on zIIP capacity, adding to the savings companies can realize by using zIIP specialty engines.

zAAP Functions

zAAPs are used to offload Web-based applications and SOA-based processing. To stay competitive, many businesses are developing strategic Web-based applications. These applications typically require more IT resources than traditional applications due to levels of abstraction, code generation, and reuse. The zAAP makes it cost-effective to run these applications on the mainframe and provides an execution environment for SOA-based technologies, further lowering costs.

In some cases, Java integration and XML parsing services workloads on z/OS also can be offloaded to the zAAP. For Java workloads, the zAAP can help customers simplify and reduce server infrastructures by integrating Java Web applications with strategic data for high-performance, reliability, availability, and security. Increased system productivity is achieved by reducing the demands and capacity requirements on general-purpose processors. Making them available for reallocation to other workloads also can extend mainframe longevity.

The general-purpose processor savings will vary based on the amount of Java application code zAAPs execute. This depends on the amount of Java cycles the relevant applications use and on the zAAP execution mode.

zAAPs are designed to operate asynchronously with the general processors to execute Java programming under control of the IBM Java Virtual Machine (JVM). The IBM JVM processing cycles can run on the configured zAAPs with no anticipated modifications to the Java applications. However, it’s important to pay attention to Java application optimization, since Java on a distributed server is designed to use all the memory available on that server. On a mainframe, the situation is different. Loops and calls to library functions need to be examined and optimized for the mainframe. There isn’t a one-to-one correlation between optimization on the two different types of processors.

Execution of the Java applications on zAAPs, within the same z/OS Symmetric Multiprocessing (SMP) Logical Partition (LPAR) as their associated database subsystems, can simplify the server infrastructures and improve efficiency. Using zAAPs reduces the number of TCP/IP programming stacks, firewalls, and physical interconnections and their associated processing latencies. In this manner, zIIPS and zAAPs support application servers and their database servers as deployed.

WinterGreen Research TCO/ROI Calculator

It can be challenging to understand the savings that can accrue by using specialty engines. To help simplify this process, WinterGreen Research has developed a TCO/ROI calculator that’s useful for aiding application platform decision-making and computing the transaction chargeback costs to the line of business for various levels of processing (see Figure 1). You choose from a list of the servers and software being used, and the calculator uses a set of assumptions from analysts and independent organizations to calculate costs based on your supplied numbers.

A demo of the calculator will show you how the savings are computed and the various input parameters available. To see a working demo of the calculator, please go to and click on “Start Demo Session,” which is highlighted in yellow on the right side of the page.


zIIPs and zAAPs have made it possible to rethink the common practice of purchasing significant amounts of processing power to ensure enough capacity for peak workloads. Today, companies can carefully purchase only what they need to ensure their processing capability is maximized at all times and budget dollars are used pragmatically. zIIPs and zAAPs help companies costeffectively expand the processing power of the mainframe while keeping TCO as low as possible.