15.1 - Processors, Parallel Processing, Virtual Machines Flashcards
(17 cards)
1
Q
Features of CISC
A
- Complex instruction set computer
- Uses multicycle instructions
- Instructions can be of variable length
- Has programmable control unit
- Requires complex protocol
2
Q
Features of RISC
A
- Reduced instruction set computer
- Uses single cycle instructions
- Uses fixed length instructions
- Uses many registers
- Uses simple instructions
3
Q
Describe the use of piplining
A
- Allows several instructions to be processed simultaniously
- Execution of an instruction is split into stages
- Each subtask can be completed during one clock cycle
- Therfor increasing number of instructions completed per unit of time
- No two subtasks can execute thier same subtask during the same clock cycle
4
Q
Explain how interupt can effect the operation of piplined processor
A
- Once processor detects an input
- All intructions appart from the last one are discarded
- Current state is saved
- Interupt service routine handles interupt
- After interupt processor restores its previous state
- Processur resumes as normal
5
Q
SISD
A
- Single instruction single data
- Only one processor
- executing the same instruction
- On the same set of data
5
Q
SIMD
A
- Single instruction multiple data
- Several processors
- Executing the same instruction
- On the same set of data
6
Q
MISD
A
- Multiple instruction single data
- Several processors
- Executing different instructions
- On the same set of data
7
Q
MIMD
A
- Multiple instruction multiple data
- Several processors
- Executing different instructions
- On the same set of data
8
Q
Describe what is meant by massively parallel computers
A
- Large number of processors
- Working collabirativly on the same prorgam
- Working together simultaniously on the same program
- Communicating via message interface
- It has a network infastructure
9
Q
What is a virtual machine
A
- An emulation of an exisiting operating system
- A computer operating system running with another computer operating system
- Using software to implement hardware setup
10
Q
What is a host operating system
A
- The operating system that is controlling the physical hardware
- The operating system for the physical
- Guest operating system is running under the host operating system
11
Q
What is a hypervisor
A
- Virtual machine software that creates and runs virtual machines
- Creates/Deletes/Manages virtual machines
- Translates instructions used by the guest operating system to the host operating system
11
Q
What is a guest operating system
A
- An operating system running in a virtual machine
- Controls the virtual hardware
- Operating system is being emulated
12
Q
Benefits of virtual machine
A
- New systems can be tried on different virtual hardware, without the need to buy the hardware
- More than one computer system can be emulated, allows multiple operating systems to coexist on a single computer
- Only one set of hardware is required, so reduces cost
13
Q
Limitations of virtual machines
A
- Use of virtual machines means execution of extra lines of code, so processing time increased
- May not be able to emulate some hardware, so that hardware can not be tested
- Time and effort required for implementation
14
Q
Role of virtual machine software
A
- Create/Delete virtual machines
- Translates intstructions used by guest operating system to that required by the host operating system
- existing hardware made available to guest operating system
15
Q
Describe what happens after the guest opereating system receives a data request from the application
A
- Guest operating system handles the request as if it were running on its own physical machine
- Handles request as usual
- Input/Output requests are translated by the virtual machine software, into instructions exacutable by host operating system
- Host operating system retreives data from file, and passes data to the virtual machine software
- Virtual machine passes data to the guest operating system
- Guest operating system passes data to the application
