#mutex

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Hello Learners! Today, we are going to cover all possible stuffs about what is mutex in OS (Operating System) and their examples with ease. This is unique article over the internet. So making ensure that at the end of this post; you will definitely fully educate about Mutex in Operating System without getting any hindrance.

‘Mutex in OS’ Tutorial Headlines:

In this section, we will show you all headlines about this entire article; you can check them as your choice; below shown all:

What is Mutex in OS?

How Does Work Mutex in OS?

Types of Mutex Locks

Components of Mutex Locks

Example of Mutual Exclusion

Applications & Uses of Mutex in OS

Advantages of Mutex in OS

Disadvantages of Mutex in OS

Solve: Producer-Consumer Problem with Example

FAQs (Frequently Asked Questions)

Why is Mutex Important in OS?

Why mutex is faster than semaphore?

Why mutex is required?

What Does mutex prevent deadlock?

Can Mutexes be used across different processes?

I just went through a situation that’s pretty useful as an analogy for mutexes in computer science.

Suppose, say, your grandpa is sick in the hospital, and your mom, your dad, and you all want to visit him and wish him well. But to slow the spread of disease, only one visitor may visit any given patient at the same time.

First mom receives the permission slip from the desk, so that she can visit grandpa, then she returns it to the counter so that dad can take it. Next it’s your turn once he’s done with his visit.

Those permission slips are the mutex flags in this analogy. Just as you can’t go into your grandpa’s room without the permission slip, you can’t access the locked resource without the mutex flag.

Arc

위는 잘못된 코드 (타이포 borrow_mut() )

Rc는 쓰레드와 같이 사용할수 없다는 것을 보여준다.

thread safe가 되기 위해서는 Send, Sync 두개다 가져야 한다

위와 같이 RefCell의 경우는 Send는 있지만 Sync는 없으므로 thread safe 가 아님

Arc , Mutex 같이 사용하기

위 작동하는 코드 (단 타이포 Arc::new(Mutex::new(0))에서  Mutex 가 아니고 RwLock이)

Arc, RwLock 같이 사용한 경우 

closure

refs_it 에서 사용된경우는  borrow 방법 (Fn 방법) my_string이 closure안에서 값이 변화되지는 않았기 때문

mutes_it 에서 사용된 경우는 FnMut 방법 이다.  my_string이 closure안에서 값이 변화되었 때문

위 맞는 코드 단( 타이포  cool_book.year % 2 == 0 )

impl trait

위 와 아래는 같은 효과

Box

위 array는 스택에 만들어지기 때문에 빠르지만 위와 같이 대용량 사용이 불가능하다 그래서  box를 이용해 heap 대용량 데이터를 저장할수 있다

위와 같이 사용할수 있을것 같지만 사실은 아니다. 왜냐하면 데이터를 스택에 먼저 만들고 그것을 복사해서 heap에 만들기 때문이다

그래서 아래가 맞는 방법이다

box는 포인터를 스택에 저장하고 데이터는 힙에 저장하므로

모든 box의 사이즈는 8 바이트로 같다

box의 값에 접근해서 수정하는 경우 포인터와 같이 * operator를 이용한다

dyn

channel

위 타입 T 가 명시 되지 않았기 때문에 패닉

위는 타입T가 정해졌으므로 패닉하지 않음

A mutex is a locking mechanism that ensures that only one function or goroutine may access a certain area of a program at any given moment. It is an essential component of concurrency management that prevents race problems.

A race issue occurs when more than one thread seeks to access shared data.

In this tutorial, we will go through the fundamentals of constructing a mutex with the Golang sync package.

Golang Sync Package

The Golang sync package offers us tools and techniques for implementing synchronization tasks like waitgroups and mutual exclusions.