introducing PSF/MVS (continued) functional comparison (continued)

PSF/MVS exclusives

235

migration effort

235

 

 

introduction

 

 

 

 

to console operation

443

to DL/I and IMS/VS 169

to sizing

13

 

 

 

to test environments

419

to VSAM differences

110

introductory documentation

39

inventory validation

492

 

 

IOREG

293

 

 

 

 

IPCS

 

 

 

 

 

 

analyzing dumps

473

 

 

analyzing traces

474

 

 

traces

474

 

 

 

using IPCS

474

 

 

 

ISAM

52, 97, 258, 326

 

 

ISASIZE

337

 

 

 

ISMF

22

 

 

 

 

 

ISPF

22, 161, 390

 

 

 

creating applications

440

executing applications

 

440

orienting ICCF 437

 

 

overview

390

 

 

 

SCLM

440

 

 

 

SDSF

437

 

 

 

utilities

439

 

 

 

ISQL

179

 

 

 

 

ISV products

417, 539

 

 

ISV system management products OS/390 539

VSE 539

J

JC statements (MVS) 84

JCL

See also Job Control Language comment lines 77 comparing VSE & MVS 91 comparing VSE and MVS 86 conditional 73, 84 conditional MVS JCL 84 conversion 33

conversion tools 492

differences and considerations 69 differences with JECL 241

DISP parameter 344 expansion 76

final conversion 516

help for hidden JCL problems 79 hidden 78

imbedding 72

JECL differences 241 job layout 72 OUTPUT statement 84 overrides 76

JCL (continued) parameter handling 75 partition dependent codes 81 problems 79 procedure/library imbedding 72 procedures 81

processing 25 return codes 73 sample MVS 93 sample VSE 92 similarities 72 SORT statements 375 standards 409 statement 72 statement continuation 72 summary of MVS statements 88 variables 73

via procedures and libraries 72 VSE - MVS differences 73 VSE statements 82

VSE versus MVS 73 VSE/ESA philosophy 70

JCL differences (VSE and MVS) catalogs (VSAM only) 81 communication region

DATE 81

UPSI 82

comparison VSE - MVS JCL 86 device address specifications 80 hidden JCL

carry-over 79

help for hidden JCL problems 79

permanent assignments & POWER defaults 79 standard labels 78

JCL expansion

early error detection 76 overrides 76

JCL partition dependent codes data set names 81 procedures 81

job input

data driven Output segmentation 75 JCL parameter handling 75 multiple instream dataset input 74

MVS JCL summary 88 MVS Job Control statements

COND parameter 85 DD statement 84

IF THEN ELSE ENDIF statements 84 MVS conditional JCL 84 OUTPUT JCL statement 84

operator intervention comment lines 77 correcting invalid syntax 76 data entry 76

PAUSE statement 77 resource allocation

allocation at OPEN time 78

Index 603

Page 627
Image 627
IBM OS/390 manual Ipcs, Isam, Isasize, Ismf Ispf, Sclm, Isql, Jcl, Date Upsi

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.