What is difference between Semaphore and Mutex

Mutex is a object owned by thread who is executing in critical section whereas semaphore is a signaling mechanism.

[@whatdoyousay4236]

Although little weird, toilet is actually is a very good example for this! It's intuitive to understand that you "lock" it and that one person uses it at a time.

[@rishkum536]

I am on my way to a Computer Science degree. I have a very good professor but you explained it way better and made it easier.

[@totommymmy]

Thank you so much! The toilet is such a good example for memorizing and understanding!

[@pepe6666]

it actually really is.

[@uzairghole3025]

There can't be a better explanation than this. I luckily happened to watch this as my first video while studying the mutex vs semaphore concepts and I can say that it took me only the duration of this video to understand the very core principle associated with this topic. Thank you.

[@burhanmuhyiddin4372]

Thank you very much :) I also confused about the difference between mutexes and semaphores and you explained the difference very clearly.

[@tedz2usa]

Beautiful explanation! I always had trouble understanding semaphores intuitively until you provided the brilliant bathroom key analogy!!

[@TheLPfunnTV]

You might have just saved my exams grade! I understood the explanation with the metaphore so much better and it sticks. Thank you!

[@omargamal2148]

don't think there's any saving if you call it a metaphore

[@TheLPfunnTV]

@@omargamal2148 good one!

[@majidsaeidi7760]

most clearly example to know mutex and semaphore. Thanks

[@camelcase9310]

believe or not your bathroom analogy helped me understood and finished my homework! Thank you so much.

[@MultiShiv19]

Watch at 1.25x speed

[@shivangikansal8025]

me too :D

[@basantachaulagain6104]

1.5x works fine for me

[@Darieee]

I watched this at 20x guys .. I think I win

[@omairbhore]

I darieee you to watch it in 40x

[@BloodHaZaRd666]

1.25 almost english, at 2 becomes japanese

[@SportsIncorporated]

Great explanation. Made it all simple. For someone without a computer science degree, me.

[@nishantchauhan1548]

Of all possible examples in the world, you chose a toilet...

[@weirdopersonnal]

hahahaha!

[@justaninfiredperson]

Nishant Chauhan 😂

[@Teslacoil33]

Lock(mutex) "Do Work" Unlock(mutex)

[@mariumahmed4567]

😂😂😂😂👏🏻👏🏻

[@shovon9412]

Of all examples the toilet will probably be most memorable

[@notoppland]

Very clear and easy to follow explanation, thank you!

[@ifxzrvz1706]

thank you, your explanation is one of the best.

[@saadmanahmed860]

very very tributary illustration. great video. the idea of mutex and semaphore really come to me translucid now

[@payalsagar1808]

honestly thankyou so much for this perfect example☺.... the concept got cleared

[@dboothe7889]

Great work! I now understand the difference the night before my exam. Many thanks Sir!

[@SubcribetoTin]

Thanks! Simple and straight to the point.

[@HowTomakeitdone]

thanks welcome to the channel.

[@lmnefg121]

dude, you are a genius to use the toilet and key as the metaphor here.

[@seba_duran]

thanks for the video, now I understand better

[@HowTomakeitdone]

Welcome to the channel

[@pepe6666]

thank you for explaining this in terms of people using the toilet. its a great example. i finally get that a semaphore is basically just an atomic integer and a waiting-mechanism really. speaking of which i need to go park a turd now. thanks very much and wish me well for my crap

[@Shifter21000]

Very good explanation! Crisp and clean .

[@HowTomakeitdone]

thanks

[@sureshkumarkaushik6109]

Thanks for this video and it helps us to understand the main concepts in best way. and easy to remember the conepts.

[@HowTomakeitdone]

Thanks Welcome to the channel.

[@medhm2262]

My frend its nice exemple it will stell in my memory for ever tanks

[@sent4dc]

All I could understand is "toilet."

[@PK-xe6sm]

A few times during this video I've been wondering if he did still use English

[@unknownuser6143]

sent4dc 😂😂😂😂

[@nishik332]

Did u pass in the exam

[@badger6431]

Because you are full of s-hit.

[@XEQTIONRZ]

The only issue with your explanation is that when a mutex is locked, another thread trying to access the mutex doesn't get returned an error as you say. It just waits until the mutex is unlocked. I think you get it, just worded it improperly. Otherwise good video.

[@muhammadwasif881]

In implementation Mutex generates busy wait and starvation so I think he is right..!

[@muhammadwasif881]

to avoid this busy wait you need to do this... [s] is the flag/switch mov ax, 0 xchg as, [s] comp ax, 0 JNZ exit sleep exit

[@wildglorypsn]

not necessarily...starvation doesn't happen often.

[@subhashishsen6157]

use mutex_try_lock() instead of mutex_lock()

[@daisysunshine6606]

thanks for the explanation i was confused

[@Penguinsxz]

Thanks for the awesome review!

[@HowTomakeitdone]

welcome to the channel.

[@jonathanazzopardipaul5048]

This was a great explanation, thanks!

[@pengxiaohan3371]

Very clear explanation. Thanks!

[@047gauravkumartiwari5]

A clear and lucid explanation!

[@arthurimona5901]

Thanks buddy for the informative video!

Very Good.Keep it up :)

[@HowTomakeitdone]

Welcome to channel.

[@sumitkaushik1942]

HowTo सपना

[@andresperez4698]

muchisimas gracias.. me quedo bien claro...gracias a ud

[@suyashvishnoi6157]

Now i clearly understand. Thank you sir

[@HowTomakeitdone]

glad to know that :-)

[@kevinfernandez2269]

He probably went to a dollar general where you have to get a key from the register for the bathroom.

[@Teslacoil33]

For the semaphore, if all the keys are identical what's to stop a person opening an occupied toilet door?

[@killstriker64]

thanks a lot for this explanation! you are awesome!

[@HowTomakeitdone]

You are welcome.

[@wilsonfarias9248]

Thank you for the video!

[@kartikpodugu]

I didn't understand clearly. Is there a specific reason we used 4 toilets and 4 keys for Semaphore example ? If we want to understand the difference, we need to have same no. of toilets for both mutex and semaphore ? Also, if 4 toilets are there, and you take the key to use toilet, then also it looks like there is ownership. What is the advantage if we have same kind of key for all 4 bathrooms ? Isn't semaphore example same as having 4 mutexes for 4 toilets ? I can't imagine what is the advantage of having same key for all 4 toilets, Please help me understand.

[@TL-fe9si]

what about P(mutex)V(mutex)? Does the semaphore now have ownership issues?

[@CoreDump451]

Wonderful explanation. Thank you! :)

[@TellaTrix]

Appreciate for your explanation!

[@Light-th1co]

how can I close a mutex in a process? Tell me please how can I do it in a batch file or per cmd.exe.

[@shrimatkapoor2200]

I still don't understand if the keys are identical, couldn't two threads access the same object and cause a race condition?

[@OlliS71]

Every mutex is built on top of a semaphore with the addition of an atomic for the fast path. The fast path makes uncontended locking in userspace possible with a small number of instructions.

[@anikettiwari6885]

If two threads will try to access data with the help of semaphore at same time race condition can come. How can we avoid it

[@prithvisinh]

Excellent presentation.

[@paulohanded28]

what software did you use to do the animation?

[@HowTomakeitdone]

This is simple PowerPoint presentation

[@ameyzulkanthiwar9148]

very nice expiation..Thank you..

[@MinhTran-sl7kc]

Thank you Raja, I understand now.

[@adharshmohan9249]

good explanation. Thanks..

[@wssz112]

love that pictures!!!!! thank you

[@peimanfarshbaf7522]

best explanation i have ever seen

[@vivekthakkar5276]

How can someone dislike this video?

[@aizazulhaq4702]

Yeah sure... cz there is a toilet in the video as an example.. duhhh

[@zhengrui315]

I really like this toilet, sorry i mean tutorial

[@zhengrui315]

@@blazkowicz666 seriously? you are picking a fight over this comment? I have no idea why it's offending to you

[@blazkowicz666]

@@zhengrui315 I thought that was something Racist implied before I watched the video. I have deleted the comment 🤝

[@UdayKumar-zm4ft]

🤣🤣🤣

[@akhilkandibanda]

awesome toilet example, i clearly understood

[@gaborm4767]

What is the benefit of mutex over semaphore?

[@jeyko666]

10/10, indian enough that it was a good tutorial!

[@a2zuser1]

Thank you very clear was useful

[@enkr1]

5:43 is it comparing if it is equal to zero not less than ..?

[@michaelcrainiciuc]

Still very good explanation that made me understand, thank you

[@shovon9412]

Great video very clear

[@kuroketanItem]

thanks man , great example and explanation :thumb_up:

[@HowTomakeitdone]

Thank you and welcome to the channel

[@zxuiji]

Welp, I found a way to ignore both of those, here's a snippet from what I'm currently constructing to give you an idea: ``` dint Send_AndWaitAll( THREAD *thread, OBJECT *object ) { BRANCH *branch = GrabThreadBranch( thread ); if ( !thread ) return 0; if ( thread != &main_thread ) { SIGNAL *signal = GrabThreadSignal(thread); OBJECT tmp = {0}; bool redo = false; object->que = time(NULL); signal->i = *object; while ( 1 ) { YieldOther(); /* Check if the thread sent us a signal */ if ( signal->o.que < object->que ) continue; /* Check if the signal was the one we were expecting */ if ( signal.o.sig != SIGNAL_CONT ) { tmp = signal->o; redo = true; continue; } break; } if ( redo ) { tmp.que = object->que; tmp.sig = SIGNAL_REDO; signal->i = tmp; } } Send_AndWaitAll( branch->Init, sig, object ); return Send_AndWaitAll( branch->Next, sig, object ); } ```

[@baqtronic7704]

Seems a good explanation, but I struggled very hard to understand this english... Subtitles would be very nice (not automatic...)

[@daisysunshine6606]

is english your second language? maybe thats why it was hard.

[@warrenpeterson5709]

yeah i couldn't understand it either. My professor used this video as required watching but im gonna search for something else I can understand.

[@anilkinikar]

Very good explanation.

[@mujjumaaz2008]

Easily understood.

[@loinguyen.youtube]

Thank you thank you so much!

[@HowTomakeitdone]

you are welcome.

[@bluesteel1]

Very very nice explanation

[@amithstark8946]

very well explained

[@bharat_india12]

Watching this for tomorrow interview

[@jammy2003]

Thanks so much!

[@rtm0076]

Best explanation ever

[@abhirajtyagi9244]

thankyou sir for this video

[@matthiaswolf2288]

great Video!

[@SriLakshmi3395]

Thanks a billion times.....U have such an awseome talent of explaining the most difficult stuff in the easiest possible way..... Before watching ur videos ,I struggled with Computer science.... Ur channel & ur way of simple easy teaching increased my passion for Computer Science...I wish u all success & healthy happy life.. God bless u.. :-)

[@HowTomakeitdone]

Thanks for nice comment It's really great.

[@unknownuser6143]

Good tutorial

[@koti571bulasara4]

good explanation

[@pavanisivadath9813]

good work in making the pictures

[@HowTomakeitdone]

thanks Welcome to the channel.

[@rogerzheng2814]

So isn't mutex just a special case of a semaphore?

[@rajattandon5692]

Great explanation

[@DEV-gz3nk]

what is mutex datatype

[@fatemakhalfan6980]

very useful...Thanks

[@Iamnoone56]

bhut umdaa

[@tanaygupta632]

I want difference between mutex and binary semaphore.

[@harshapalanki5491]

Is binary semaphore and mutex same???

[@mywtfmp3]

Very good. But I think you need to explain why mutex use ownership while semaphore use signaling mechanism.

[@HowTomakeitdone]

+echo Mutex allow only one process/thread to access shared data because of that it need to lock that object. Whereas semaphore multiple processes can be allowed and in order to notify them for availability of data signaling mechanism is used. Welcome to channel.

[@AhmadKhanNaul1]

Very very well method

[@poojasingh-nw3mv]

thanks for the video.....

[@HowTomakeitdone]

Thanx for appreciating

[@openyourmind1694]

Every theoric book says these things; I'd like to find a modern c++11/14 implementation. In real pratice we can't code description of the ideas but what we need are implementations

[@voipims]

This video is half....people do have confusion between mutex and binary semaphore

[@farruhhabibullaev5316]

What? Toilet example is funny one, Good explanation...

[@afraimlevi9871]

Thank U

[@lavanyabellamkonda7399]

nice video.thank you

[@HowTomakeitdone]

thanks

[@ibknl1986]

Good example.

[@teuton8363]

Thanks for the video, but please buy a good microphone. If video quality is bad thats one thing but audio quality should always be good, otherwise people tune out quickly.

[@HowTomakeitdone]

thanks for your concern. I will improve audio definitely.

[@KNT_19]

In case of semaphore, if the two threads accessing a shared resource, there will be race condition. Can tell, in this case, how synchronization is achieved?

[@HowTomakeitdone]

If you want only one resource to be accessed at one time then you need to take semaphore value accordingly.

[@gauravhiran6747]

Use java "synchronised" keyword.

[@ashishchauhan8494]

Thanks for video

[@HowTomakeitdone]

you are welcome Ashish.

[@blockobutter]

My textbook had so much abstraction and bullshit beating-around the bush with fornal words that I didn't understand anything. All I needed was the toilet example, with multiple keys.

[@Mohammed-fk9dj]

4 identical keys for the toilet!!! what if somebody already in toilet and another person come and open the toilet! LOL

[@petermako3174]

maybe the locks work in a way, that if somebody inserts the key into the lock from the inside it prevents turning the other key from unlocking the door

[@TT-ud5gf]

This is the best question :)