Draft Document for Review April 7, 2004 6:15 pm

6947ch07.fm

to perform a normal Data Base Management System (DBMS) restart - not DBMS recovery - at the opposite site. GDPS/XRC is application-independent and therefore covers the customer's complete application environment.

Site 1

 

Site 2

11 12

1

 

 

10

 

2

 

 

9

 

3

 

 

8

 

4

 

 

7

6

5

 

 

 

 

 

 

Recovery

Application

 

Application

 

Systems

 

 

SDM System

Systems

 

Systems

 

 

 

Data mover

 

 

 

Channel

 

 

 

CF01

Extenders

 

 

 

 

CE

 

SW

 

 

CE

SW

 

 

 

CE

Secondary

 

 

 

volumes

 

 

 

CE

and SDM

Control Data sets

Primary

volumes

Figure 7-11 GDPS/XRC

The physical topology of a GDPS/XRC, shown on Figure 7-11, consists of a production site (Site 1) and a recovery site (Site 2) located virtually at any distance from Site 1.

GDPS/XRC is capable of the following attributes:

￿Disaster recovery

￿RTO between one and two hours

￿RPO less than two minutes

￿Protects against metropolitan as well as regional disasters (distance between sites is unlimited)

￿Minimal remote copy performance impact

In a GDPS/XRC configuration, it is often necessary to have multiple System Data Movers (SDMs) - the number of SDMs is based on many factors, such as the number of volumes being copied, the I/O rate, and so on. Functions are now capable of being executed in parallel across multiple SDMs, thus providing improved scalability for a coupled SDM configuration.

7.4.3 GDPS and Capacity Backup (CBU)

GDPS consists of production images and controlling images. The production images execute the mission-critical workload. There must be sufficient processing resource capacity, such as processor capacity, main storage, and channel paths available that can quickly be brought online to restart an image's orsite's critical workload. Typically this is accomplished by terminating one or more systems executing expendable (non-critical) work and acquiring their processing resource.

The Capacity Backup (CBU) feature, available on the zSeries, provides a significant cost savings. The CBU feature has the ability to increment capacity temporarily, when capacity is

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IBM 990 manual Site, Gdps and Capacity Backup CBU, Application, Systems, Recovery
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990 specifications

The IBM 990 series, often referred to in the context of IBM's pioneering efforts in the realm of mainframe computing, represents a unique chapter in the history of information technology. Introduced in the late 1960s, the IBM 990 series was designed as a powerful tool for enterprise-level data processing and scientific calculations, showcasing the company's commitment to advancing computing capabilities.

One of the main features of the IBM 990 was its architecture, which was built to support a wide range of applications, from business processing to complex scientific computations. The system employed a 32-bit word length, which was advanced for its time, allowing for more flexible and efficient data handling. CPUs in the IBM 990 series supported multiple instructions per cycle, which contributed significantly to the overall efficiency and processing power of the machines.

The technology behind the IBM 990 was also notable for its use of solid-state technology. This provided a shift away from vacuum tube systems that were prevalent in earlier computing systems, enhancing the reliability and longevity of the hardware. The IBM 990 series utilized core memory, which was faster and more reliable than the magnetic drum memory systems that had been standard up to that point.

Another defining characteristic of the IBM 990 was its extensibility. Organizations could configure the machine to suit their specific needs by adding memory, storage, and peripheral devices as required. This modular approach facilitated the growth of systems alongside the technological and operational demands of the business environments they served.

In terms of software, the IBM 990 series was compatible with a variety of operating systems and programming environments, including FORTRAN and COBOL, enabling users to access a broader array of applications. This versatility was a significant advantage, making the IBM 990 an appealing choice for educational institutions, research facilities, and enterprises alike.

Moreover, the IBM 990 was engineered to support multiprocessing, which allowed multiple processes to run simultaneously, further increasing its effectiveness in tackling complex computing tasks.

In summary, the IBM 990 series represents a significant advancement in computing technology during the late 20th century. With a robust architecture, versatile configuration options, and a focus on solid-state technology, the IBM 990 facilitated substantial improvements in data processing capabilities, making it a cornerstone for many businesses and academic institutions of its time. Its impact can still be seen today in the continued evolution of mainframe computing.
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