GATE 2023 CSE Exam | Operating Systems | Introduction to Synchronization
| Free Online Course
BYJU'S Exam Prep GATE & ESE: EE,EC,IN,CS
Anshul: Those who are aiming for gate 2023 do n't miss this class and
this entire series because this is the most important topic in operating
system and we are going to cover the concepts plus the questions. After
attending these classes you don't have to refer again any other lecture
for this i can tell you that. In inter process communication we talk
about two types of processes. One process can affect the result of
another process also so we can say they are sharing some yes yes this is
the first lecture of os yes aisha so in case of uh cooperating processes
one can impact the result. One is your shared memory and other one is
your message passing so these are the two mechanisms we follow. Message
passing involves system calls that means whenever system calls are there
os intervention will be there. Message passing is useful for exchanging
smaller amounts of data so if you want to send some data which is very
small to another process so you can use message passing and it is easier
to implement also as compared to shared memory.
Have two methods for message passing we have direct method we have
indirect method. Direct message passing is there direct and indirect and
if you talk about shared memory. In indirect it is not using in indirect
they just directly refer to the ports utkash. The reason is the reason is
to avoid to avoid data inconsistency. At assembly level you can see this
count plus plus plus is nothing but these set of instructions is it clear
everyone so far now let 's talk about this count minus minus minus now
here you can. i 'm showing you here is how we can have how why we need
synchronization between these two processes so carefully carefully listen
this. P2 process has updated the value of count from four to three clear.
P2 is going to read the incorrect value because for p2 the correct value
the updated value should be 3 but what it is getting is getting five. In
this case we are going to have data inconsistency the one process will be
reading the wrong value.
A sequence of one or more statements that appears to be indivisible that
is no process will interrupt the operation that is atomic operations. A
section of code within a process that requires access to be shared
resources and that must not be executed while another process is in a
corresponding code. A situation in which two or more processes are unable
to proceed because each is waiting for one of the others to do something
but they are not doing clear so that is the situation of deadlock. The
final result of count will be decided by the order of process execution
so starvation starvation is basically a situation where both processes
are hungry. There are four conditions that need to be satisfied if you
are proposing any synchronization solution now let 's talk about it one
by one. The first condition we have is mutual exclusion the first
condition must be clear before proceeding to synchronization mechanisms.
The last but not the least the fourth condition is your architectural
neutrality.
No more than one process should be able to enter into the critical
section we can say yes mutual exclusion is satisfied second is progress
| Free Online Course
BYJU'S Exam Prep GATE & ESE: EE,EC,IN,CS
Anshul: Those who are aiming for gate 2023 do n't miss this class and
this entire series because this is the most important topic in operating
system and we are going to cover the concepts plus the questions. After
attending these classes you don't have to refer again any other lecture
for this i can tell you that. In inter process communication we talk
about two types of processes. One process can affect the result of
another process also so we can say they are sharing some yes yes this is
the first lecture of os yes aisha so in case of uh cooperating processes
one can impact the result. One is your shared memory and other one is
your message passing so these are the two mechanisms we follow. Message
passing involves system calls that means whenever system calls are there
os intervention will be there. Message passing is useful for exchanging
smaller amounts of data so if you want to send some data which is very
small to another process so you can use message passing and it is easier
to implement also as compared to shared memory.
Have two methods for message passing we have direct method we have
indirect method. Direct message passing is there direct and indirect and
if you talk about shared memory. In indirect it is not using in indirect
they just directly refer to the ports utkash. The reason is the reason is
to avoid to avoid data inconsistency. At assembly level you can see this
count plus plus plus is nothing but these set of instructions is it clear
everyone so far now let 's talk about this count minus minus minus now
here you can. i 'm showing you here is how we can have how why we need
synchronization between these two processes so carefully carefully listen
this. P2 process has updated the value of count from four to three clear.
P2 is going to read the incorrect value because for p2 the correct value
the updated value should be 3 but what it is getting is getting five. In
this case we are going to have data inconsistency the one process will be
reading the wrong value.
A sequence of one or more statements that appears to be indivisible that
is no process will interrupt the operation that is atomic operations. A
section of code within a process that requires access to be shared
resources and that must not be executed while another process is in a
corresponding code. A situation in which two or more processes are unable
to proceed because each is waiting for one of the others to do something
but they are not doing clear so that is the situation of deadlock. The
final result of count will be decided by the order of process execution
so starvation starvation is basically a situation where both processes
are hungry. There are four conditions that need to be satisfied if you
are proposing any synchronization solution now let 's talk about it one
by one. The first condition we have is mutual exclusion the first
condition must be clear before proceeding to synchronization mechanisms.
The last but not the least the fourth condition is your architectural
neutrality.
No more than one process should be able to enter into the critical
section we can say yes mutual exclusion is satisfied second is progress
