CS 3321 - Exam I

List several defining characteristics of the z/OS operating system.

(i) process large number of concurrent batch jobs with automatic load balancing. (ii) manage mixed workloads (iii) manage large i/o configuration of thousands disk drives, printers, and terminals

How does z/OS differ from a single-user operating system? Give two examples.

(i) process large workloads (ii) can allow thousands of user transaction concurrently

Characteristics of an online transaction are: A) Uses a small amount of input data and demands a fast (usually less than one second) response B) Entered by a large number of people during well defined business hours (e.g. 9am to 5pm) C) Entered by a few people and so has little need for security D) Entered in groups (batches) by highly trained business employees E) Uses a small amount of input data and runs for a long time

A

Since its introduction in 1964, the IBM mainframe has A) Evolved and in many ways leads in delivering modern computing technologies B) Remained stagnant C) Evolved and incorporates some modern computing technologies D) Evolved but only supports 32 bit addressing; PC's support 64 bit addressing E) Evolved but only supports "green screen" terminals and interfaces

A

The "360" in the name "System/360" is a reference to what? A) The 360 degrees of a compass B) The revenue expected to be generated by S/360 sales ($360 Million) C) None of the above D) The projected number of systems that were expected to be sold (360) E) Nothing, it is an arbitrary number that "sounds good" for marketing

A

The concept of blocked data or blocking has to do with: A) How data is physically arranged on a storage device B) How the catalog entry for a data set is recorded C) How data is logically arranged on a storage device D) How data is manipulated by a program E) How data is presented to a program

A

The z/OS acronym RAS stands for A) Reliability, Availability, and Serviceability B) Random and Secure C) Receive and Send D) Real as Storage E) Random Access Storage

A

Which two operating systems are the most prevalent operating systems running on System z mainframes? A) z/OS and Linux for zSeries B) z/VM and Linux for zSeries C) zTPF and z/VM D) z/OS and VSE E) VSE and z/VM

A

What is a partitioned dataset?

A PDS is a collection of sequential datasets called members.

What is a library in z/OS?

A library refers to a PDS or a PDSE

What is the difference between master and user catalog?

A master catalog stores catalog information of dataset system dataset and aliases for user catalogs. user catalogs store catlog information of user datasets.

A System z technique that allows multiple simultaneous operations of two or more programs under the control of one copy of z/OS is called A) SMO (symmetric multioperations) B) SMP (symmetric multiprocessing) C) Multiprogramming D) SMT (symmetric multithreading) E) Clustering

B

An enterprise is about to upgrade an older System z server to the latest technology mainframe. This enterprise has a program that was witten 20 years ago, is still in use, and the source code for the program is no longer available. What should the enterprise expect relative to the old program when the server upgrade occurs? A) They should expect to contact IBM to make sure that the operating system services that the program uses are still supported B) They should expect that the program will run without any changes C) They should expect that they will have to find the source code and recompile the program so it will work with the new server D) They should expect that the new server will recognize that the old program is down level and return an error code E) They should expect that they will have to upgrade the program so it will work with the new server

B

How would you characterize the physical size of a mainframe computer (not including its I/O (or peripheral) equipment)? A) About the size of a pickup truck B) About the size of a large refrigerator C) About the size of a large hotel ballroom D) About the size of a desktop computer E) About the size of a microwave oven

B

Two distinguishing characteristics of mainframe computing are: A) Secure and outdated B) Secure and highly available C) Large scale (capacity) and outdated D) Highly available and cumbersome E) Secure and Expensive

B

Which customer enterprises would likely be interested in the System z On/Off Capacity on Demand feature? A) Customer enterprises that would like to deploy new applications with temporary extra capacity B) All of the above C) Customer enterprises that would like to pilot new applications with temporary extra capacity D) Customer enterprises with a need for predictable short term capacity growth E) Customer enterprises with a need for unpredictable capacity growth

B

A System z technique whereby several programs appear to execute concurrently is called A) SMP (symmetric multiprocessing) B) SMT (symmetric multithreading) C) Multiprogramming D) TCMP (tightly coupled multiprocessor) E) SMO (symmetric multioperations)

C

All of the data that can be read or written without moving all of the read/write heads of a disk device (DASD) is referred to as: A) Volume B) Circle C) Cylinder D) Cartridge E) Track

C

If a fixed block physical record is 1000 bytes long and the records are recorded in blocks of 10, how long is each fixed length record (i.e. what is the logical record length)? A) 50 bytes B) 1010 bytes C) 100 bytes D) 10,000 bytes E) Can't tell with the information provided

C

Many z/OS system programmers who have worked with z/OS for a long time still refer to it using its original (old) name: A) MFT B) RAS C) MVS D) SRB E) VSE

C

Which mainframe job/role would you expect to perform software customization, capacity planning and performance tuning? A) End User B) Application Developer C) Systems programmer D) System Operator E) Database Administrator

C

Name the two broad categories of workload likely to be found running on a mainframe. ANSWER Explanation for E. these are applications, not workloads A) Batch and Spreadsheets B) Spreadsheets and Word Processing C) Data Mining and Simulation Games D) Batch and online transaction processing E) Payroll and Inventory

D

What is a dataset? What types of data sets are used on z/os?

Dataset refers to a file that contains one or more records. The record is the basic unit of information used by a program running on z/OS. Types of datasets: (1) Partition Dataset (PD and PD-E) (2) Sequential Dataset (SD and SD-E) (3) VSAM

What is a DASD volume?

Datasets in Z/OS are organized into DASD volumes. They are used of storing datasets.

A programmer has 40 sequential data sets. The 40 datasets collectively represent a program that will be used by a business. Which z/OS dataset type should the programmer use to store the datasets? A) 40 sequential files B) Four PDS datasets each with ten members C) 20 sequential files D) A VSAM KSDS E) One PDS

E

A z/OS catalog is: A) A place to store free space information B) A collection of VTOCs C) A dataset used to store information about z/OS users D) A collection of extents E) A dataset used to store location information about other datasets

E

Mainframes are most extensively used by what type of businesses? A) Small/medium businesses B) Local "mom and pop" stores C) Only the "Fortune 10" D) Home based businesses E) Large corporations

E

Two common z/OS units of work are: A) SMTs and tasks B) SRBs and ENQs C) Tasks and SLOTs D) SRBs and PSWs E) Tasks and SRBs

E

Typical z/OS "middleware" would include A) End user application programs B) z/OS itself C) Java SDK D) auxiliary storage E) Database software and web server software

E

How are dataset named in z/OS.

Each dataset name is unique which is up to 44 chars. A dataset name consists of segments names also called level qualifier. The first segment is called the HLQ (high level qualifier), and last segment is called LLQ (low level qualifier). Each name is 1 to 8 characters long. Each name must begin with a character A-Z or @, #, or $ followed by zero or more characters, numbers, or hyphens. All names have only upper case letters.

What is the difference between byte stream file system and record-oriented file system?

In a byte stream file system, files are just a collection of sequential streams of bits, and there is a special character to tell the computer where a line (or record) ends and the next one begins. In a record-oriented file system, files are organized on the disk into separate records. With record-oriented files, you explicitly define the sizes and attributes of your records, so there is no need for a special end line character, which helps conserve system resources

What is "virtual" about virtual storage?

It gives the illusion that the system has more storage than it has physically.

What is a sequential dataset?

It is a data structure for storing data in z/os. It consists of one or more records.

What are the various VSAM datasets?

Key Sequenced Datasets, Entry Sequenced datasets, Relative Record sequenced dataset, and Linear Datasets.

Match the following terms: a. Page ___ auxiliary storage b. Frame ___ virtual storage c. Slot ___ central storage

Match the following terms: a. Page _c_ auxiliary storage b. Frame _a_ virtual storage c. Slot _b_ central storage

Multiprocessing means running several processors simultaneously (available to the operating system and applications). What does multiprogramming mean?

Multiprogramming is running of more than one program simultaneously on the same processor.

What z/OS application changes are needed to work in a Parallel Sysplex?

One or more CFs (coupling facilities)

What is a PDSE?

PDSE is a partitioned dataset extended which basically the same as PDS with additional functionality to expand or remove storage space as needed.

Virtual address format and the how to determine the the RX, SX, PX, and BX components form a given 64 bit virtual address.

RX: 33 bits SX: 11 bits PX: 8 bits BX: 12 bits Convert the hex number to binary to get bits

Tell in one line each, what is (a) System z (b) z/OS (c) z/VM ?

System z is a large scale computer system or mainframe computer built by IBM. z/VM is a base virtual machine building s/w (software) that is installed on top of the h/w (hardware). z/OS is a 64-bit operating system for a mainframe computer within a z/VM.

A number of non-mainframe computer systems are available today which claim to be "mainframe like" or provide the same value as mainframes. A) True B) False

T

The S/360 eliminated several problems that were inherent in computers that preceded it including: the inability to upgrade to a larger computer, proprietary and incompatible peripheral interfaces, and the ability to run both engineering and commercial work on the same computer. A) True B) False

T

The death of the mainframe has been greatly exaggerated. A) True B) False

T

Why does the power needed for a traditional COBOL application not have a linear relationship with the power needed for a new Java application?

The power of a system is often linked to the cost of software licensing. The power needed to run a COBOL application does not have a linear relation to that of running a new Java application because the cost of adding a new Java application increases non-linearly.

How are VSAM files stored?

They are stored in control intervals consisting of one or more records.

What are the differences between loosely coupled systems and tightly coupled systems?

Tightly coupled systems contain multiple processors (CPUs) that are connected by channels. They have access to a centrally shared memory or may participate in a memory hierarchy with both local and shared memory. Loosely coupled system has multiple stand-alone units/processors interconnected via high speed communication systems.

How to allocate PDS and PDS members from and ISPF panel?

To allocate a PDS using ISPF on the Option line: =3.2 and enter On option line enter: A (for allocate) On the Name line enter the name of the dataset that we are creating: 'C3321XX.DATASET', XX is the last two digits of your id Volume serial (enter one of them): VPWRKA, VPWRKB, VPWRKC, VPWRKD (I prefer VPWRKA) and press enter In the next panel type the following and press enter: Data Set Name . . . : C332100.DATASET Management class . . . (Blank for default management class) Storage class . . . . (Blank for default storage class) Volume serial . . . . VPWRKA (Blank for system default volume) ** Device type . . . . . (Generic unit or device address) ** Data class . . . . . . (Blank for default data class) Space units . . . . . TRKS (BLKS, TRKS, CYLS, KB, MB, BYTES or RECORDS) Average record unit (M, K, or U) Primary quantity . . 10 (In above units) Secondary quantity 5 (In above units) Directory blocks . . 6 (Zero for sequential data set) * Record format . . . . FB Record length . . . . 80 Block size . . . . . 32720 Data set name type PDS (LIBRARY, HFS, PDS, LARGE, BASIC, * EXTREQ, EXTPREF or blank) Extended Attributes (NO, OPT or blank) Expiration date . . . (YY/MM/DD, YYYY/MM/DD Enter "/" to select option YY.DDD, YYYY.DDD in Julian form Allocate Multiple Volumes DDDD for retention period in days or blank) ( * Specifying LIBRARY may override zero directory block) ( ** Only one of these fields may be specified) When you hit enter, if successful you will get the message on the top right "Data set allocated" Similarly, you can also allocate a sequential data set to the PDS you have just now created: on the Option line: =2 and enter In the next pannel enter the name of the member you wish to edit. on the line Other Partitioned, Sequential or VSAM Data Set, or z/OS UNIX file: Name . . . . . 'C332100.DATASET(HELLO)' + and press enter.

What z/OS application changes are needed for it to work in an LPAR?

Type 1 Hypervisor

List several differences and similarities between the z/OS and UNIX operating systems.

UNIX z/OS differences: (i) boot the system IPL the system (ii) Files and directories Sequential datasets and partitioned datasets (iii) bytes oriented format record format similarities Run application in Java, C, COBOL, and soon Both systems allow data stored in memory to be shared among processes. Both systems have the concepts of virtual memory managements.

What is the difference between a UNIX file and Z/OS dataset?

Unix files are store as text files or binary files. Text files are sequence of bytes separated by carriage return. Binary files are stored as a sequence of binary words. In Z/OS, datasets are stored as logical records. Executable modules are stored undefined records.

What is a VTOC? what is a catalog?

VTOC stands for volume table of content. It is a list of dataset that resides on the volume along with information about its location and size of each dataset and other attributes. A catalog describes the dataset name, attributes, and indicates the volume on which it a located.

What role does workload management play in a z/OS system?

Workload management manages the processing of workloads in the system according to the business goals. It manages the use of system resources such as processor and storages to achieve throughput (optimal uses of the system), response and turnaround time.

List the three major types of storage used by z/OS.

i) DASD (direct access storage device) volumes (ii) tape cartridges (iii) Virtual tape or virtual disk.