Describe about address space and memory space, Computer Engineering

Assignment Help:

Q. Describe about Address Space and Memory Space?

An address used by a programmer will be termed as a virtual address and set of such addresses the address space. An address in main memory is known as a physical address. The set of these locations is termed as memory space. So address space is set of addresses produced by programs as they reference instructions and data, memory space comprises actual main memory locations directly addressable for processing.

Supposes a computer which has a main-memory capacity of 64K words (K=1024). 16-bits are required to specify a physical address in memory because 64K = 216. Assume that computer has auxiliary memory for storing information equivalent to capacity of 16 main memories. Let's signify address space by N and memory space by M we then have for this illustration: N = 16 × 64 K = 1024K and M = 64K.

In a multiprogramming computer system, data and programs are transferred to and from auxiliary memory and main memory based on demands obliged by CPU. Suppose program 1 is currently being executed in CPU. Program 1 and a part of its associated data are moved from secondary memory in the main memory as displayed in Figure below. Parts of programs and data require not being in contiguous locations in memory because information is being moved in and out and empty spaces may be available in scattered locations in memory.

1319_Describe about Address Space and Memory Space.png

Figure: Address and Memory Space in Virtual Memory

In our illustration address field of an instruction code will comprise 20 bits however physical memory addresses should be specified with just 16-bits. So CPU will reference data and instructions with a 20 bits address though information at this address should be taken from physical memory since access to auxiliary storage for particular words will be prohibitively long. A mapping table is then required as displayed in Figure below to map a virtual address of 20 bits to a physical address of 16 bits. Mapping is a dynamic operation that means every address is translated instantly as a word is referenced by CPU.  

323_Describe about Address Space and Memory Space1.png

Figure: Memory table for mapping a virtual table


Related Discussions:- Describe about address space and memory space

Operation research, how to implement a modified distribution method using c...

how to implement a modified distribution method using c/c++

Identifying stakeholders, I have chosen an imaginary example to illustrate...

I have chosen an imaginary example to illustrate the different stakeholder categories. At Home sells a selection of consumer products, currently listed in a paper catalogue, whi

Illustrate about the single inheritance, Illustrate about the single inheri...

Illustrate about the single inheritance During inheritance, superclass feature may by override by a subclass defining that feature with the same name. The overriding features (

Write an interrupt routine to handle division by zero, Q. Write an interrup...

Q. Write an interrupt routine to handle 'division by zero'? This file can be loaded just like a COM file though makes itself permanently resident until the system is running.

How many number of flip flops contained in IC 7490, The number of flip flop...

The number of flip flops contained in IC 7490 is ? Ans. 2 flip flops contained in IC 7490.

Learning abilities of perceptrons - ann, Learning Abilities of Perceptrons ...

Learning Abilities of Perceptrons - Artificial intelligence Computational learning theory is the study of what concepts specific learning schemes (representation and method) ca

Define TII, TII stands for? Ans. TII stands for Table of incomplete ins...

TII stands for? Ans. TII stands for Table of incomplete instructions.

4 bit comparator, how to breadboARD THE 4 BIT COMPARATOR

how to breadboARD THE 4 BIT COMPARATOR

Find how many bits of adc are required to get an resolution, Find how many ...

Find how many bits of ADC are required to get an resolution of 0.5 mV if the maximum full scale voltage is 10 V Ans. Given Resolution=.5mV Full scale output=+10v %resolut

Find max conversion time of 6-bit dual slope A/D converter, A 6-bit Dual Sl...

A 6-bit Dual Slope A/D converter uses a reference of -6V and a 1 MHz clock. It uses a fixed count of 40 (101000). Find Maximum Conversion Time.         Ans. The time T 1 specifie

Write Your Message!

Captcha
Free Assignment Quote

Assured A++ Grade

Get guaranteed satisfaction & time on delivery in every assignment order you paid with us! We ensure premium quality solution document along with free turntin report!

All rights reserved! Copyrights ©2019-2020 ExpertsMind IT Educational Pvt Ltd