Self Doubt

Question

I think TSL has bounded Waiting

==> Consider p0 and p1 , p0 exiting from Critical Section(CS) by setting flag=0

and now p1 can easily enter in CS , It’s not TSL’s fault that p1 is starve to get CPU so p1 can enter in CS

it’s scheduling algo’s fault , Assumed we implemented Round Robin then no such issue arise

 

Even Peterson Solution is unbounded wait if not implemented with round robin.

Comments

@iamkingukiddo

Peterson's algorithm  is a concurrent programming algorithm for mutual exclusion that allows two or more processes to share a single-use resource without conflict, using only shared memory for communication ...

While Peterson's original formulation worked with only two processes, the algorithm can be generalized for more than two...

 

 

## Any solution to the critical section problem must satisfy three requirements:

Mutual Exclusion : If a process is executing in its critical section, then no other process is allowed to execute in the critical section.

Progress : If no process is executing in the critical section and other processes are waiting outside the critical section, then only those processes that are not executing in their remainder section can participate in deciding which will enter in the critical section next, and the selection can not be postponed indefinitely.

Bounded Waiting : A bound must exist on the number of times that other processes are allowed to enter their critical sections after a process has made a request to enter its critical section and before that request is granted…

 

## Peterson’s Solution :

Peterson’s Solution is a classical software based solution to the critical section problem…

In Peterson’s solution, we have two shared variables:

** boolean flag[i] :

Initialized to FALSE, initially no one is interested in entering the critical section ….

•  int turn : The process whose turn is to enter the critical section…

 

 

## Filter algorithm: Peterson's algorithm for more than two processes :

The filter algorithm generalizes Peterson's algorithm to N > 2 processes…

Instead of a boolean flag, it requires an integer variable per process, stored in a single-writer/multiple-reader atomic register, and N − 1 additional variables in similar registers....

 

1. https://gateoverflow.in/18743/Scheduling-algorithm 

and

https://gateoverflow.in/18743/Scheduling-algorithm?show=362656#c362656 

 

2. http://www2.cs.uregina.ca/~hamilton/courses/330/notes/synchro/node3.html 

 

3. https://gateoverflow.in/178434/Bounded-wait 

 

4. https://gateoverflow.in/163027/Process-synchronisation 

 

5. https://gateoverflow.in/169795/Critical-sections-conceptual 

 

6. https://gateoverflow.in/154798/Peterson-solution