Download z/VM Conversational Monitor System (CMS)

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z/VM
Module 2: Conversational Monitor System (CMS)
© 2004 IBM Corporation
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Objectives
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List z/VM’s base components and describe how they work together
Describe CMS and the tasks it can accomplish
State why CMS Pipelines are an important feature of z/VM
Describe CMS Application Multitasking
Describe the XEDIT environment and its purpose
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Objectives continued
 Describe the three important application environments that CMS
supports:
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– Callable Service Library (CSL)
– OpenExtensions
– Reusable Server Kernel
Show how to find and use the Help Facility
Explain Shared File System (SFS) setup and configuration
Explain how syntax diagrams are used
List and describe the most important and useful CMS commands
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Introducing z/VM’s Base Components
 Conversational Monitor System (CMS)
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An end-user interface for running user programs
 Control Program (CP)
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A component that manages the resources of a single system to make it
appear that multiple computing systems exist
 REXX/VM
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A programming language that allows you to write customized application
programs and command procedures
 Group Control System (GCS)
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A virtual machine supervisor that provides multitasking services
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Introducing z/VM’s Base Components continued
 Transparent Services Access Facility (TSAF)
 APPC/VM VTAM Support (AVS)
 Virtual Machine Serviceability Enhancements Staged/Extended
(VMSES/E)
 Dump Viewing Facility
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What is CMS?
 Conversational Monitor System is an operating system
environment itself
 Over time CMS became a part of VM
 CMS is a single user operating system, which makes it possible
to:
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Create and maintain files
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Write and execute application programs
 CMS communicates with users through the console
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CMS Tasks
With CMS, you can:
 Write, test, and debug application programs for use on CMS or guest
systems
 Run application programs developed on CMS or guest systems
 Create and edit data files
 Process jobs in batch mode
 Share data between CMS and guest systems
 Communicate with other system users
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Structure of CMS
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Callable Services Library (CSL)
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CMS Pipelines
 Provide a rich and efficient set of functions that can be used to
solve large problems by breaking them up into smaller programs
 Smaller programs are called stages
 Stages:
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Read data
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Filter and refine data
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Combine multiple data items
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CMS Pipelines
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Pipeline Example
pipe < profile exec | count lines | console
 This command executes the number of lines contained within your
PROFILE EXEC file.
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CMS Application Multitasking
 An application can be divided into multiple units of execution,
called threads.
 Threads have the ability to run on multiple CPUs at the same time
 Multitasking facilities allow applications to harness the power of the
underlying multiprocessor complex to achieve high performance.
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OpenExtensions
 OpenExtensions provides open systems support in two ways:
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OpenExtensions Services
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OpenExtensions Shell and Utilities
 OpenExtensions Services include:
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POSIX.1—System Interfaces
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POSIX.1a—Extensions to POSIX.1
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POSIX.1c—Threads
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OpenExtensions – Invocation
 Invocation from REXX Procedures example
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OPENVM is a z/VM subcommand environment
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OPENVM makes invocation of callable services look like other
requests for host functions
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The OPENVM language binding file defines REXX variables used by
the OpenExtensions services. You include the file using the
APILOAD function.
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Reusable Server Kernel
 Enables vendors and application programmers to write multithreaded
server programs
 The server kernel is the starting point for a server program
 To construct a server program you need:
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A text library of routines
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A macro library of function prototypes
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Constant definitions
 These entities are supplied by the Reusable Server Kernel
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Additional RSK Help Areas
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Connectivity
DASD I/O
Authorization
Memory management
Runtime environment
Worker machines
Configuration and operation
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XEDIT
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XEDIT continued
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XEDIT continued
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The Batch Facility
 Can take over both short and long processing jobs for you
 Frees up your time to continue working at your terminal
 Two examples:
– Have the facility format text and send it to the printer, instead of doing it
yourself
– Have large jobs run throughout the night to take advantage of lower
computing costs
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How the VM Batch Facility Works
 The process starts when you submit a job to the VM Batch Facility
 The monitor virtual machine receives your job and holds it until it can
start
 A task virtual machine runs your job
 The monitor machine periodically checks your job while it runs
 Your commands can retrieve the status of a job, change how and when it
is to run, and cancel a job
 When your job is completed, the task machine logs off and is ready for
another job
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z/VM Help Facility
 CMS Help Facility provide assistance for:
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Tasks
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Commands and options
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Subcommands
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REXX statements
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Callable routines
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Pipeline stages
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Assembler language macros
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Messages
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Shared File System (SFS)
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Files are stored in file pools
A user can be given an amount of file space in a pool
The files in a file space are organized in directories
A file can be placed in more than one directory
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Shared File System (SFS) continued
 Users can grant each other authorities for files or directories
 Multiple users can have concurrent access to the same file or
directory
 Locks on files and directories ensure data integrity among multiple
users
 You can share files and directories with users on other systems
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Syntax Diagrams (basics)
 Read syntax diagrams from left to right and from top to bottom
 This side module shows you descriptions and examples
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CMS Commands
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QUERY
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QUERY – Usage Notes
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SET
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ACCESS
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ACCESS
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ACCESS – Usage Notes
 Using the ACCESS command with a directory ID or a device
number
– With and without a file pool
 Using the ACCESS command with a directory ID
– Determining status by ownership
 Using the ACCESS command with a virtual device number
– Access can create a file directory in your virtual machine when one is not
present
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RELEASE
 The RELEASE Command is used to free an accessed disk that was
previously accessed with the ACCESS Command.
 Example:
release
0293
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RELEASE
 If you want to release and detach the 498 disk that is accessed as your
file mode b, then issue:
release
498 (det
OR
-- release b (det
 To just release the disk currently accessed as file mode c, issue:
release
c
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FORMAT
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FORMAT – Usage Notes
 Examples of RECOMP and LABEL:
– format 192 b (recomp)
– format 193 c (label)
 Formatting a disk requires heavy processor utilization, so can be slow and
affect performance
 Choose the appropriate block size to optimize:
– space utilization
– performance
 Automatic formatting is possible on the 192 disk
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Conclusion
 CMS – Conversational Monitor System
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Is a operating system that runs within z/VM
 CMS tasks include writing, testing, and debugging application
programs to be used by CMS or z/VM guest systems
 CMS runs the full-screen editing facility called XEDIT
 The CMS help facility is a CMS Command that can be accessed
when help is needed by entering:
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help cms
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Glossary
Conversational Monitor System (CMS)- A component of z/VM that runs in
a virtual machine and provides both the interactive z/VM end-user
interface and the general z/VM application programming interface. CMS
runs only under the control of the z/VM Control Program (CP).
CMS Pipelines- CMS job control product for z/VM that enables complex
tasks to be specified and executed. CMS Pipelines has three parts – a
command parser, a library of built-in programs, and a dispatcher.
Callable Services Library-A package of CMS routines that can be stored
as an entity and made available to a high-level language, REXX, or an
assembler program.
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Glossary
File pool-A collection of minidisks managed by a file pool server. It contains
user files and directories and associated control information. The files and
directories for many users can be contained in a single file pool.
Group Control System (GCS)- A component of z/VM, consisting of a
named saved system that the user can IPL and run in a virtual machine. It
provides simulated MVS services and unique supervisor services to help
support a native SNA network.
Initial Program Load (IPL)- The process of loading an operating system
into a machine
OpenExtensions Services- The VM implementation of three POSIX
standards
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Glossary
OpenExtensions Shell and Utilities- provides application development
tools and an interactive environment in support of the POSIX application
environment.
REXX/VM- (REstructed eXtended eXecutor programming language)
processes English-like commands.
XEDIT- A full-screen editing facility that runs under CMS.
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References
 CMS Command and Utility Reference. Manual Number: SC246010-02. Third Edition (May 2002).
 CMS User’s Guide. Manual Number: SC24-6009-00. First Edition
(July 2001).
© 2004 IBM Corporation