ZSeries Application Assist Processor, Z/OS Scalability

goals, WLM can adjust processor capacity, channel paths, and I/O requests across LPARs without human intervention.

IRD assigns resources to the application; the applica- tion is not assigned to the resource. This capability of a system to dynamically direct resources to respond to the needs of individual components within the system is an evolutionary step. It enables the system to continuously allocate resources for different applications, and this helps to reduce the total cost of ownership of the system. IRD is made up of three parts that work together to help optimize the utilization of zSeries resources:

•LPAR CPU Management

•Dynamic Channel Path Management

•Channel Subsystem Priority Queuing

The z/OS Intelligent Resource Director (IRD) Planning Wizard helps to plan your IRD implementation by asking questions about your enterprise setup, and produces a worksheet that describes the issues on each of your systems that you must consider before you can implement IRD. The z/OS IRD Planning Wizard supports z/OS 1.2 and higher.

zSeries Application Assist Processor

The IBM ^zSeries Application Assist Processor (zAAP), available on the z990 and z890 servers, is an attractively priced specialized processing unit that pro- vides an economical Java execution environment for z/OS for customers who desire the traditional qualities of service and the integration advantages of the zSeries platform.

When conﬁ gured with general purpose processors within logical partitions running z/OS, zAAPs may help increase general purpose processor productivity and may contrib- ute to lowering the overall cost of computing for z/OS Java technology-based applications. zAAPs 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 the demands and capacity requirements on general purpose proces- sors which may then be available for reallocation to other zSeries workloads.

The IBM JVM processing cycles can be executed on the conﬁ gured zAAPs with no anticipated modiﬁ cations to the Java application(s). Execution of the JVM processing cycles on a zAAP is a function of the Software Developer’s Kit (SDK) 1.4.1 for zSeries, z/OS 1.6, and the Processor Resource/Systems Manager (PR/SM).

z/OS Scalability

z/OS is a highly scalable operating system that can sup- port the integration of new applications with existing mainframe applications and data. z/OS can scale up in a single logical partition, or scale out in a Parallel Sysplex for higher availability. With z/OS V1.6, up to 24 processors are supported in a single logical partition on the z990 server. In previous releases, z/OS supported up to 16 processors. In a Parallel Sysplex, up to 32 z/OS images can be conﬁ g- ured in single-image cluster, with access to shared data.

64-bit Support

z/OS scale is extended with support for 64-bit real and virtual storage on zSeries servers, while continuing to sup- port 24-bit and 31-bit applications.

The 64-bit real support is intended to eliminate expanded storage, helps eliminate paging and may allow you to consolidate your current systems into fewer LPARs or to a single native image. z/OS 1.5 delivers 64-bit shared memory support to allow middleware to share large amounts of 64-bit virtual storage among multiple address spaces. This is expected to provide a signiﬁ cant capacity enhancement for relieving shared virtual storage constraints.