z Systems Application Assist Processor (zAAP)

Today's reality

To remain competitive in the market today's businesses and organizations are developing new mobile, web and other applications that can consume more resources than traditional applications due to the use of higher level languages, Java, XML, etc.

Those applications can be effectively processed by special purpose engines such as the IBM z Systems Application Assist Processor (zAAP), or the IBM z Systems Integrated Information Processor (zIIP).

NOTE: Beginning with IBM z13, zIIP specialty engines will be used to process both zAAP-eligible work and zIIP-eligible work. Customers should plan to run all zAAP-eligible workloads on zIIP processors.

The z13 offers increased capacity (with up to 141 configurable cores) and also offers a new optionally configurable SMT (simultaneous multithreading capability) to run up to two concurrent threads per core. SMT is supported on zIIP specialty engines and on IFLs on the z13.

SMT is designed to provide more predictable capacity, deliver repeatable performance across varying levels of CPU utilization, and can deliver improved price performance for zIIPS.

What it does

The IBM z Systems Application Assist Processors (zAAPs) are available on all IBM zEnterprise EC12/BC12, IBM zEnterprise 196/114, IBM System z10, and IBM System z9 servers.

zAAP specialty engines, (and zIIP specialty engines) provide an attractively priced execution environment for web-based applications and SOA-based technologies, such as:

See the page Support for zAAP Processors

What it means


For Java workloads, zAAPs, and now zIIPs, may enable customers to:

When configured with general purpose processors within logical partitions running z/OS, zAAPs,and now zIIPs, may help increase general purpose processor productivity and may contribute to lowering the overall cost of computing for z/OS Java technology-based applications. zAAPs and zIIPs are designed to operate asynchronously with the general processors to execute Java programming under control of the IBM Java Virtual Machine (JVM). This can help reduce capacity requirements on general purpose processors which may then be available for reallocation to other mainframe workloads.

The IBM JVM processing cycles can be executed on the configured zAAPs, or now zIIPs, with no anticipated modifications to the Java application(s).

The amount of general purpose processor savings will vary based on the amount of Java application code executed by zAAPs (or zIIPs).

Execution of the Java applications on zAAPs, and now zIIPs, within the same z/OS LPAR as their associated database subsystems, can also help simplify the server infrastructures and can improve operational efficiencies. For example, use of zAAPs, or zIIPs, could help reduce the number of TCP/IP programming stacks, firewalls, and physical interconnections (and their associated processing latencies) that might otherwise be required when the application servers and their database servers are deployed on separate physical server platforms.

IBM does not impose software charges on zAAP or zIIP capacity. Additional IBM software charges apply only when additional general purpose CP capacity is used. Customers are encouraged to contact their specific ISVs/USVs directly to determine if their charges will be affected.

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