Explain peterson''s solution for the critical section problem, Operating System

Assignment Help:

Explain the Peterson's solution for the critical section problem?

In Peterson's solution two variables a) flag and b) turn are used as shared variables. If the both shared variables are set after that particular process can get into the critical section. Or else it gives other processes to get into the critical section and consider the segment for a process Pi to get into the critical section.

         do

            {

               flag[i]=true

               turn=j

               while(flag[j]&&turn==j)

               critical section

               flag[i]=false

               remainder section

            }while(1)

 

code segment for a process Pj is as follows:-

do

            {

               flag[j]=true

               turn=i

               while(flag[i]&&turn==i)

               critical section

               flag[j]=false

               remainder section

            }while(1)

 

            When flag[i]=true and turn=j is implemented, let a context switch take place. Therefore the control comes to the process Pj. therefore the statement flag[j]=true is executed. Again a contest switch take place and control is now with Pi. Therefore when the while condition is checked both of the conditions are true. Therefore while condition is true always and it ends up in an infinite loop. Therefore Pi is in an infinite loop and waits till the condition gets false. Therefore Pj executes here first and makes flag[j]=false. Therefore when a context switch occurs, Pi will get into its critical section. Implementation of each process depends on the context switch occurring between the two processes.


Related Discussions:- Explain peterson''s solution for the critical section problem

What is preallocation, What is preallocation? Why do it? Allocating spa...

What is preallocation? Why do it? Allocating space for a file before making the file to allow for expansion. This reserves space for a certain file so that other files can't gr

Explain about file allocation methods, Explain about file allocation method...

Explain about file allocation methods? The main problem in direct-access nature is how to assign space to these files so that disk space if utilized effectively and files can b

Estimate the balking rate, People arrive at a barber shop at the rate of on...

People arrive at a barber shop at the rate of one every 4.5 minutes. If the shop is full (it can hold five people altogether), 30% of the potential customers leave and come back i

Explain time-sharing environment, In a multiprogramming and time-sharing en...

In a multiprogramming and time-sharing environment, several users share the system simultaneously. This situation can result in various security problems. a

Define virtual memory, Define Virtual memory Virtual memory is employe...

Define Virtual memory Virtual memory is employed in all major commercial operating systems

Illustrate the operating system components, Q. Illustrate the Operating Sys...

Q. Illustrate the Operating System Components? Modern operating systems share the goal of supporting system components. System components are: 1.  Process Management 2.

Difference between sam and active directory, Question: (a) Write down ...

Question: (a) Write down short notes on the different versions of Windows server 2003 mentioned below: 1. Windows Server 2003, Web Edition 2. Windows Server 2003, Stand

Hashed page table, Hashed page tables A common approach for handling ad...

Hashed page tables A common approach for handling address spaces larger than 32 bits is to use a hashed page table. Every entry in the hash table having a linked list of elemen

Mechanism for code and data sharing, Q. Consider a system in which a progr...

Q. Consider a system in which a program is able to be separated into two parts: code and data. The CPU recognizes whether it wants an instruction (instruction fetch) or data (data

What are the main challenges for mobile computing, Question: (a) What ...

Question: (a) What are the main challenges for Mobile Computing? (b) What is the ISM band and what is particular about this frequency band? Name two wireless technologies

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