Distributed Operating Systems - Operating System Fundamentals

Front 1

What are the 4 primary goals of an operating system?

Back 1

1) efficiency - getting operations done as quickly as possible
2) Flexibility - friendliness and freedom
3) Consistency - uniformity in using the system, maintains integrity with concurrency control, and maintains data integrity.
4) Robustness - failure prevention and recovery

Front 2

What is access transparency?

Back 2

The ability to access both local and remote system objects in a uniform way. Physical separation of objects is concealed from the user.

Front 3

What is location (name) transparency?

Back 3

Users have no awareness of object locations. Objects are mapped and referred to by logical names.

Front 4

What is migration transparency (location independence)?

Back 4

Added property of location transparency where an object is not only referred to by its logical name but can also be moved to a different physical location without changing the name.

Front 5

What is concurrency transparency?

Back 5

Allows the sharing of objects without interference.

Front 6

What is replication transparency?

Back 6

Consistency of multiple instances of files and data.

Front 7

What is parallelism transparency?

Back 7

Permits parallel activities without users knowing how, where, and when activities are carried out by the system.

Front 8

What is failure transparency?

Back 8

Provides fault tolerance such that failures in the system can be transformed into graceful performance degradation rather than disruptions, and damage to the user is minimized.

Front 9

What is performance transparency?

Back 9

Attempts to achieve a consistent and predictable performance level even with changes to the system structure or load distribution.

Front 10

What is size transparency?

Back 10

Allows incremental growth of a system without the user's awareness.

Front 11

What is revision transparency?

Back 11

Software changes in the system are not visible to the user. Refers to the vertical growth as opposed to horizontal growth in system size.

Front 12

What transparencies support efficiency?

Back 12

Concurrency, Parallelism, and Performance transparency support this

Front 13

What transparencies support flexibility?

Back 13

This is supported by access, location, migration, size, and revision transparency

Front 14

What transparencies support consistency?

Back 14

This is supported by access, replication, and performance transparency.

Front 15

What transparencies support robustness?

Back 15

This is supported by failure, replication, size, and revision transparencies.

Front 16

What are the 3 fundamental functions that a kernel must provide?

Back 16

Communication, synchronization, and processor multiplexing.

Front 17

What is processor multiplexing (process serving)?

Back 17

Managing creation, deletion, and tracking of processes by allocating the necessary resources such as memory and processing time.

Front 18

What is a name server used for?

Back 18

This is used to locate user processes or machines

Front 19

What is a directory server used for?

Back 19

This is used to locate files and communication ports

Front 20

What synchronization is done with physical clocks?

Back 20

Clock used to keep operations synchronized or to request that an operation be processed at a certain real time.

Front 21

What synchronization is done with logical clocks?

Back 21

Clock used to maintain ordering of events to ensure the correctness of operations that depend on each other.

Front 22

What are the three types of entities in an OS?

Back 22

The three types are processes, files, and communication paths (ports).

Front 23

What is the processor pool model?

Back 23

System model in which users access a virtualized single computer system with intelligent terminals.

Front 24

What are the 7 layers of the OSI protocol suite?

Back 24

1) Application
2) Presentation
3) Session
4) Transport
5) Network
6) Data link
7) Physical

Front 25

What are the 4 layers of the TCP/IP protocol suite?

Back 25

1) application/process
2) transport
3) internet
4) data link/physical layer

Front 26

What 2 tcp/ip layers does a gateway have?

Back 26

This has only the internet and data link/physical layer.

Front 27

What is barrier synchronization?

Back 27

This is where a set of processes must reach a common synchronization point before they can continue.

Front 28

What is condition coordination?

Back 28

This is where a process must wait for a condition set by other interacting processes to maintain ordering of execution.

Front 29

What is mutual exclusion?

Back 29

This is where concurrent processes have exclusive access to a critical shared resource.

Front 30

What is a network operating system?

Back 30

A loosely coupled multi-computer system where no direct hardware or software control of one workstation to another exists, and the communication cost is higher than the internal data transfer within each workstation.

Front 31

What is a centralized operating system?

Back 31

The traditional operating system for single/multiprocessor architectures. Tightly coupled in that all resources are shared internally and the interprocess communication is achieved through either memory sharing or direct process interrupts.

Front 32

What is a distributed operating system?

Back 32

A system in which physical resources are distributed by the inherent nature of a loosely coupled system. Information is automatically distributed. Hides implementation details from the users of the system. Many users getting different services from the same system.

Front 33

What is a cooperative autonomous system?

Back 33

System that abolishes the notion of a single user view of a multiple computer system. Each user or process operates autonomously by exporting and requesting services. Many users getting the same service from different systems.

Front 34

What is the ultimate goal of a distributed operating system?

Back 34

Making it possible to maintain a uniform programming paradigm.

Front 35

In what 4 ways are rpc and local procedures syntactically different?

Back 35

1) handling of connection setup
2) parameter marshaling
3) exception handling
4) logical view of execution environment

Front 36

What is the major advantage of Java RMI?

Back 36

It allows object passing and dynamic invocation of objects.

Front 37

What are the synchronization facilities of a monitor?

Back 37

Wait, notify, and notify all on conditions

Front 38

What are two caching approaches for name servers?

Back 38

1) Client caches the higher level name servers
2) Server caches the lower level name servers in sub-domains

Front 39

What are two approaches for replication in name server caches?

Back 39

1) Push based - server sends out global cache updates
2) Pull based - client requests local cache updates

Front 40

What are the ACID properties primarily concerned with?

Back 40

Concurrency transparency

Front 41

What are the 4 ACID properties?

Back 41

Atomicity, Consistency, Isolation, Durability

Front 42

Atomicity

Back 42

All or none of an operation is performed, in spite of failures

Front 43

Consistency

Back 43

Like serializability, the execution of interleaved transactions is equivalent to serial transactions in some order.

Front 44

Isolation

Back 44

Partial results are not visible to others before a transaction is complete

Front 45

Durability

Back 45

System guarantees that committed transactions are permanent