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

Difference between preemptive and nonpreemptive scheduling, Define the diff...

Define the difference between preemptive and nonpreemptive scheduling. State why strict nonpreemptive scheduling is unlikely to be used in a computer center. Preemptive schedul

Packets and time division multiplexing (tdm), Broken data into small packet...

Broken data into small packets allow time division multiplexing. In TDM every packet leaves the sender and is switched on the shared interaction channel through a multiplexer. At t

Semaphore, mention the three problems that mat be caused by wrong initializ...

mention the three problems that mat be caused by wrong initialization and placement of wait() and signal()operations in the use of semaphore

What are the issues in designing a network, Normal 0 false fa...

Normal 0 false false false EN-US X-NONE X-NONE MicrosoftInternetExplorer4

DMA block diagram, I need help,i want a brief and easy explanation to under...

I need help,i want a brief and easy explanation to understand and write in exams and easy to understand topic of DMA block diagram which Is of I/O management and scheduling? can u

Enforce memory protection at compile time?, Why is it not possible to enfor...

Why is it not possible to enforce memory protection at compile time?   Every process should be protected against unwanted interference by other process, whether intentional or

How many page faults take place in lru replacement, Q. Consider the subseq...

Q. Consider the subsequent page reference string: 1, 2, 3, 4, 2, 1, 5, 6, 2, 1, 2, 3, 7, 6, 3, 2, 1, 2, 3, 6. How many page faults would take place for the following replace

Define seek time and latency time, Define seek time and latency time. T...

Define seek time and latency time. The time taken by the head to move to the appropriate cylinder or track is known as seek time. Once the head is at right track, it must wait

Virtual memory and paging, A- Consider a computer system that provides a vi...

A- Consider a computer system that provides a virtual memory space that consists of 8  pages. The physical memory contains 4 pages where the page size is 4Kbytes. Assume that at sp

What is the information associated with an open file, What is the informati...

What is the information associated with an open file? Various pieces of information are associated with  an open file which may be: File pointer Disk location of th

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