/XRL/18

 

i

(1) changes between VSE and OS/390

 

 

 

24, 24, 25, 25, 25, 25

C020005

2043VARS

 

 

 

i

(1) approaches to migration

 

 

 

27, 27, 27, 28, 29, 29, 29, 30, 30

C020006

2043VARS

 

 

 

i

(1)

education

 

 

 

31, 31, 31, 31, 31

C020007

2043VARS

 

 

 

i

(1) scope of work challenges

 

 

 

32, 33, 33, 35, 37, 37

C020009

2043VARS

 

 

 

i

(1)

OS/390 documentation resources

 

 

 

39, 40, 40

C030001

2043VARS

 

 

 

i

(1)

plan development

 

 

 

41, 41, 41

C030002

2043VARS

 

 

 

i

(1)

plan components

 

 

 

45, 45, 47, 48, 49

C030003

2043VARS

 

 

 

i

(1) progressive versus mass conversion

 

 

 

49, 50, 50, 50, 50, 50, 51, 51, 51

C030004

2043VARS

 

 

 

i

(1)

plan examples

 

 

 

54, 56

C320001

2043VARS

 

 

 

i

(1)

conversion process

 

 

 

482, 483, 484, 484, 486

C320002

2043VARS

 

 

 

i

(1) mass conversion - background, benefits & method

 

 

 

486, 487, 489, 490, 490

C320004

2043VARS

 

 

 

i

(1)

preparation phases

 

 

 

494, 495, 497, 499, 501

C320005

2043VARS

 

 

 

i

(1)

conversion phases

 

 

 

503, 504, 505, 506, 506, 511, 511, 513, 514

C320006

2043VARS

 

 

 

i

(1)

implementation phases

 

 

 

516, 516, 517, 518

D010003

2043CH01

 

 

 

5

(1)

customer migration rationale

 

 

(2)

capacity constraints

 

 

 

5, 9, 9

D020002

2043CH02

 

 

 

14

(1)

sizing migration effort

 

 

(2)

areas of VSE & OS/390 differences

 

 

 

14, 14, 14, 15, 15, 16

D020004

2043CH02

 

 

 

19

(1)

OS/390 components/products/subsystems

 

 

(2)

operating environment

 

 

 

19, 19, 20, 21, 23

D030002

2043CH03

 

 

 

41

(1)

plan development

 

 

(2)

recommendations

 

 

 

41, 42, 42, 42, 42, 43, 43, 43, 44

D030004

2043CH03

 

 

 

45

(1)

plan components

 

 

(2)

team

 

 

 

46, 46, 47, 47

D030016

2043CH03

 

 

 

51

(1)

progressive versus mass conversion

 

 

(2)

complexity of implementation

 

 

 

52, 52

D030018

2043CH03

 

 

 

56

(1)

plan examples

 

 

(2)

project plan example

 

 

 

56, 58

D040003

2043CH04

 

 

 

72

(1)

JCL high level similarities

 

 

(2)

JCL statement & job layout

 

 

 

72, 72, 72, 72, 72, 72, 73, 73, 73, 73

D040004

2043CH04

 

 

 

73

(1)

JCL high level similarities

 

 

(2)

spooling

 

 

 

73

D040005

2043CH04

 

 

 

73

(1)

JCL differences (VSE and MVS)

 

 

(2)

job input

 

 

 

74, 75, 75

D040006

2043CH04

 

 

 

76

(1)

JCL differences (VSE and MVS)

 

 

(2)

JCL expansion

 

 

 

76, 76

Page 664
Image 664
IBM OS/390 manual XRL/18

OS/390 specifications

IBM OS/390, a versatile operating system, was a cornerstone in enterprise environments and played a pivotal role in mainframe computing. Released in the mid-1990s, OS/390 combined the strengths of IBM's MVS (Multiple Virtual Storage) with new features and enhancements, targeting scalability, reliability, and performance in demanding business applications.

One of the key features of OS/390 was its robust support for multiple users and processes. The system allowed thousands of concurrent users to access applications and data, ensuring high availability and minimizing downtime—a critical requirement for many large organizations. This scalability was supported through various enhancements in memory management and processor scheduling, enabling optimal resource allocation across diverse workloads.

OS/390 was known for its superior workload management capabilities. The Workload Manager (WLM) component allowed administrators to define service policies, specifying how system resources would be allocated according to the priority of tasks. This ensured that critical business processes received the necessary resources while less critical tasks were managed more flexibly.

Another significant characteristic of OS/390 was its commitment to security. The operating system provided comprehensive security features, including user authentication, data encryption, and auditing capabilities. This focus on security was vital for organizations handling sensitive data, ensuring compliance with regulations and safeguarding against unauthorized access.

OS/390 also supported advanced technologies that facilitated integration and development. The system included features like the IBM CICS (Customer Information Control System) for transaction processing and IMS (Information Management System) for database management. These technologies allowed organizations to build robust, high-performance applications tailored to specific business needs.

The ease of network integration was another strength of OS/390. With the advent of the Internet and global connectivity, OS/390 systems could easily interface with various network protocols, enabling businesses to operate in a connected world. This inclusion paved the way for many organizations to expand their capabilities and offer new services, driving digital transformation.

In conclusion, IBM OS/390 represented a significant advancement in mainframe technology, combining scalability, security, and robust workload management. Its rich feature set and support for critical enterprise applications solidified its role as a vital component of many organizations' IT infrastructures, ensuring they could meet their operational challenges head-on while supporting future growth. As technology continues to evolve, the legacy of OS/390 remains influential in the realm of computing.