C# Async/Await/Task Explained (Deep Dive)

[@rheinelroimanalo7321]

Thank you programming Jesus!

[@RawCoding]

Stay blessed son

[@sonikajha3788]

😂

[@PerryCodes]

Jesus is always pergmarily looking out for us!

[@dattabansode6598]

misunderstanding is extremely common. Many people are taught that multithreading and asynchrony are the same thing, but they are not. Example. You are cooking in a restaurant. An order comes in for eggs and toast. Synchronous: you cook the eggs, then you cook the toast. Asynchronous, single threaded: you start the eggs cooking and set a timer. You start the toast cooking, and set a timer. While they are both cooking, you clean the kitchen. When the timers go off you take the eggs off the heat and the toast out of the toaster and serve them. Asynchronous, multithreaded: you hire two more cooks, one to cook eggs and one to cook toast. Now you have the problem of coordinating the cooks so that they do not conflict with each other in the kitchen when sharing resources. And you have to pay them. Now does it make sense that multithreading is only one kind of asynchrony? Threading is about workers; asynchrony is about tasks. In multithreaded workflows you assign tasks to workers. In asynchronous single-threaded workflows you have a graph of tasks where some tasks depend on the results of others; as each task completes it invokes the code that schedules the next task that can run, given the results of the just-completed task. But you (hopefully) only need one worker to perform all the tasks, not one worker per task.

[@RawCoding]

Can you explain to me what made you think I'm misunderstanding something? To me it seems you explained what I explained but from a high level, which is what everyone does, and at no time did I make the following claim: > that multithreading and asynchrony are the same thing, but they are not. My explanation is based around - handing off a task to something else to work on, so in your example it would be a fryer (external process) frying an egg (working on a task), and we are not waiting for it (thread isn't blocked). When I go to explain that a different thread may complete the rest of our task it's like chef1 starting to cook an egg and chef 2 finishes it. If you are just giving another high level overview of asynchrony there are ton's of these, people are still looking for these videos because they want to understand the abstraction behind it. And I'll re-state I do think your explanation is correct and informative but doesn't cut where it needs to.

[@exogendesign4582]

Should've have find this comment sooner, I should learn both though. What I want was Synchronous for my project Since it depends on the completion of the first task before the next. that's why I there is no blocking in my app, since im using async, it really baffles me but this comment really made me see the difference, and the video made me understand how to right the code, good combination. Thanks for sharing your knowledge Datta Bansode. and Raw Coding you guys rock.

[@emreaka3965]

@@RawCoding You said, "another thread is indeed going to complete the boiling process." but the man says "there is no another thread. it runs single thread." If I am wrong, please correct.

[@ТарланИсмаилов-т2к]

​@@emreaka3965 I think that the number of threads depends on operation type we need to execute (IO-bound or CPU-bound). IO-bound operations don't need additional threads, they use some external devices that don't need our help. But I might be wrong

[@ZombieMagnum]

As I understand it from this video, the use of async/await DOES in fact sometimes automatically create additional threads, hoewever not necessarily for every async function or await statement. It is confusing that people insist that async/await is ''single-threaded asynchrony" when in practice it is not true. I do understand that multi-threading is a different concept, your explanation is great.

[@ragtop63]

Although I already had a pretty good understanding of how all this works, I have to say that your explanation is by far the best that I’ve seen. Too many times other videos show you some simple implementation that really can’t be ported to the real complexities of asynchronous programming. So you leave those videos with a “Hmm, ok. I guess that makes sense. But how do I apply it to my specific situation?” kind of feeling. What you’ve done here is not given us the fish but instead taught us how to fish. A fundamental understanding of complex topics is always the best method. Great job!

[@pratikzirpe315]

I haven’t seen anyone else explain such complex concept with such ease and still thorough - to the point. Thank you 🙏🏻

[@RawCoding]

Cheers!

[@PaulSebastianM]

@@RawCoding 5:53 Cheers! 😆

[@TJahmusick]

This is exactly how I wanted this explained to me. Incredible! Thanks!

[@RawCoding]

Thank you for watching))

[@aronhegedus]

this is really useful because you're showing us the inbetween code, rather than just telling us. I find that that's usually the most instructive, because I can then go and check that as well

[@mikecu2249]

This must be the Best Explanation about this Topic on our Planet! You didnt not only manage to create a crystal clear image, approch and explanation. You also picked the confused C# Devs up who still tried to figure out, what the clock is happening to my code? Thank you!

[@RawCoding]

Glad I could help!

[@aleksandermirowsky7988]

Rust's async/await functionality operates in a similar way, as it also expands into a state machine. It has been explained by Rust experts multiple times, but your explanation takes it to another level. The ability to visualize the intermediate generated code is just the icing on the cake. Great stuff, happy to see that you're still an actively posting on KZbin. Instantly subscribed and activated notifications.

[@RawCoding]

Thank you really appreciate it!

[@hsnnoznn]

Man, I usually take the information I need and close the video but you are absolute legend. I can not skip without a huge thanks. You explained it very well. Again, thanks a lot.

[@ВладимирСоколовский-щ1ы]

Dear friend. Visit youtube channel "Solve My Programming Task". They create simple programs for free. I used it. I am a student.

[@speakoutloud7293]

Man, I just can't get enough of your videos. You rock with this! Keep it up.

[@RawCoding]

Cheers, glad you liked them

[@spuriustadius5034]

I got totally confused about Dump() and Dump(string s) until I realized that you are using some kind of built in extension method that your IDE (linqpad?) somehow defines for you. Once I understood that, it was super clear.

[@RawCoding]

Awesome! glad it didn't get in the way too much :) Yeah linqpad is like a mini development environment, as you can see I get to run my code instantly instead of waiting for the app to compile/start etc... and the data vizualisation that you get through Dump can be pretty incredible :)

[@nobytes2]

pretty weird tbh, just use console write like every other human 🙄

[@RawCoding]

No

[@Jwhite1979]

100% this! I'm 1:49 into the video, and I pull out C# In A Nutshell, find nothing, Google "String dump method", find nothing, search through KZbin comments for someone, for the love of god, anyone explaining what the hell this .Dump method is all about! Thank you Spurius. Today, you're the hero.

[@RichardONeil]

@@RawCoding agreed...Linqpad is the greatest tool on my belt to quickly work things out. You get all the cruft out of the way and can hone directly in on an algorithm that you are trying to build, or understand. I highly recommend buying it to everybody that does this for a living.

[@MiningMozo]

Step 1 - Complete High school Step 2 - Complete Colleges The next step is to figure out what the fuck is going on

[@RawCoding]

Pretty much :P

[@watherby29]

Step 4 - Accept you will never know what's going on

[@pieDesert]

S-Tier explanation and demonstration. It is so difficult to find decent tutorials out there, but this one was no fat just cut right to the information I needed to hear and delivered with such simplicity. Also actually using the full time of the video to teach and explain and not self promote and advertise. Appreciate the raw commentary!

[@RawCoding]

Glad I could help)

[@michalbrndiar5317]

Crystal clear and absolutely the best explanation of this concept I've ever seen. Keep up great work! :)

[@RawCoding]

Thank you )

[@WantOxide]

Bullshit this crap is not clear

[@michalbrndiar5317]

Hmm, probably it is not this video's fault. 🤔

[@WantOxide]

@@michalbrndiar5317 of course it is. there are more clear videos, so it's clearly his video fault

[@WantOxide]

@@michalbrndiar5317 And if it's not his video's fault it means you just do spaghetti code as he does (and spaghetti explanations)

[@StreetBladerBloke]

Very clear and especially deep dive which is always a missing part in programming videos, you have nailed it.. thanks and keep it up with these videos they are pure gold..maybe u can create a course and sell it..I am sure deep dives are missing in today's programming world where instructors are just bothered about creame only but not the cake. You and Jamie king are the only ones who are taking it to another level. Thanks for ur efforts

[@RawCoding]

Cheers, there will be a course at one point

[@cuzsleepisthecousinofdeath]

Finally a person who's just like Jamie King(pardon me for making a comparison): straight to the point, showing the internal guts of things Subscribed instantly

[@RawCoding]

Cheers

[@LarrySmith1437]

Well done, sir. I struggled with how to present this topic to my dev department, your example helped a lot.

[@RawCoding]

Cheers

[@geerivana]

Your videos are way better than any other official online courses

[@RawCoding]

Cheers

[@investmentjourney7912]

Best explanation till now, not just showing windows form for ui activeness like others. 👍

[@RawCoding]

Cheers

[@dunefedaykiin]

Awesome video, like always! Looking forward to the next video about the practical use of async/await!

[@RawCoding]

Cheers ))

[@ghazanfarabbas4187]

Never seen such a insightful video before. Keep it up man...

[@RawCoding]

Thanks

[@AjitGoel]

This is a amazing video, first clear explanation of the async-await internals. Thank you Raw Coding.

[@RawCoding]

Thank you for watching

[@TheFeaz]

Hey man, this (and your other video showing HOW to use async / await) was REALLY good information. Another person said it, but I'll say it again, this was the best presentation of this material that I've ever seen. I'm a senior software engineer with my company, and I've been here almost 20 years. Most of my work is in hard-core business logic, and I haven't done a lot with system-level stuff, multi-threading, and all that. With the changing system model these days and an emphasis on micro-services, I'm re-visiting these concepts (that and I'm doing some of my own private consulting now, doing web development, Docker containers, etc. and certainly am seeing a lot of this async stuff, particularly in the bakc-channel OAuth stuff.) Anyway, the biggest challenge I have learning this stuff in a meaningful way is that content out here usually goes one of two places-- It either shows very simplistic "hello world" type examples, that make would make a great "Await / Async 101" course or a college lab project, but in practice they don't scale well to anything resembling what we would actually DO in an enterprise application. On the other hand, there are task-oriented "how-to's" that show you the how but not the WHY. I really appreciated your deep-dive into this and a look at how the MSIIL implements this. That really gave a whole new dimension to my understanding of how this stuff actually works under the covers, and gives me some much-needed insight into how I could leverage these features in our enterprise applications.

[@RawCoding]

Thank you for your comment))

[@lefrutit228]

tutorials such that are exaclty what youtube needs lol, I barely can find tutorials that I cant understand from the first watching, they're too simple, but this is excellent, thank you!!

[@RawCoding]

Thank you 🙏

[@kopilkaiser8991]

Thank you so much for taking the time to explain it. I have understood some of the concepts and I will need to rewatch it to better grasp the concepts. But still I was completely lost with this asynchronous programming, and was able to find some of the way by watching your tutorial. Thank you for simplifying the complex concepts. It takes a great mind to decode the entanglement which the async await Task brings in when you jump into it after being comfortable with synchronous programming. I will keep on digging into this until it is drilled deep into my mind.

[@ВладимирСоколовский-щ1ы]

Dear friend. Visit youtube channel "Solve My Programming Task". They create simple programs for free. I used it. I am a student.

[@jimsteinPeerless]

You do overemphasize the importance of threads like everyone trying to explain Async does. It is a nice very demo but (this is not covered by this video) if you in the first example replace the await Task.Delay(300) with a busy loop (the same as in the main function) there will not be another thread spawn and everything will execute on a single Thread. This is task concurrency on a single thread(?). Task.Delay is not CPU bound but the busy loop is CPU bound. So Task.Delay is good for simulating an IO bound Task and therefore you get continuation on another thread. The threads are operating on a layer below concurrency, so you do not need to have multiple threads to have Task concurrency(?). Kind regards

[@RawCoding]

Thank you for sharing

[@mrcalico7091]

@@RawCoding Thankfully, You're the teacher here!

[@matthewkeron1448]

schooooled him

[@ВадимН-о9х]

Can someone please explain me what Jimstein Peerless meant? As he said, i replaced "await Task.Delay(300)" with CPU bounded task (the loop shown in the video for example): await Task.Run(() => { var a = 0; for (int i = 0; i < 100_000_000; i++) { a += i; } Console.WriteLine("CPU-bound task in running on ThreadId = " + Thread.CurrentThread.ManagedThreadId); }); And i still see it being executed on another thread (Console.WriteLine shows thread id different from the main thread id). OR did he meant not using async/await and just start a raw CPU bound loop? But then it would be totally synchronous program and it is not the point of this video. But he still got so many likes on his comment. So seems like people found it useful. I am so confused...

[@RawCoding]

I guess I haven’t explained the Task.Run in this video where it’s literally a task you give the thread pool to execute, if you have a Synchronous Task method that returns a task without having async await , it will literally wait for the function to finish executing to give you the result of a Task object, like a normal function you are just waiting for the return value.

[@RawCoding]

Want to know C# as I do it? Get My C# programming course learning.raw-coding.dev/csharp-programming-course

[@_Ming_Ming_]

Thank you for this clear explaination sir! for this I will never skip ads in your video

[@RawCoding]

thank you

[@jasonherrera7605]

Thank you, it is difficult for me to follow your English, but it has been the best explanation I have ever known.

[@RawCoding]

Awesome, thank you )

[@magerehenk7579]

why is it difficult to follow his english?

[@RawCoding]

I’m not a native speaker and some other people aren’t ether, so it’s a compounding effect

[@phongs2nhu]

Good job, man. I'm from Viet Nam. So by watching your video, I studied new knowledge and English language. Of course, your voice is great with nice intensity. Thanks a million.

[@RawCoding]

Glad I could help :)

[@forbin80]

Bruhhhh... I've been reading about and even using async for a couple years now and in 20 mins you just cleared up everything I didn't understand about the way this stuff works. All the weirdness I've seen in my code now makes perfect sense. Fantastic video, I can't thank you enough. By far the most clear explanation of async/await I've ever seen.

[@RawCoding]

Thank you, glad I could help:)

[@decentwig5648]

Async has never really clicked until today, thank you very much.

[@hlazunov]

This is the insane video about async/await in .NET. I have never seen a better explanation of async in .NET. Thanks a lot.

[@oganovdavid]

Thanks so much for sharing your knowledge. Haven't met anyone explaining this better than you. I've finally got some understanding of what's going on. Subscribed

[@RawCoding]

Cheers, glad I could help :)

[@anpham871]

Thanks a lot!! You motivated me so much!! You are the best C# developer i've ever seen on youtube.

[@RawCoding]

Cheers ma dud ))

[@zhh174]

thank you so much. no one explained it on youtube. they just show the use of async and await.

[@RawCoding]

Cheers, that’s what my problem with all the tutorials were :)

[@НазарийСавиных]

Best explanation i've ever seen. Thanks!

[@RawCoding]

Ty

[@rafiul41]

One of the most underrated channels on KZbin.

[@razortier4284]

Great job. Not so many guys are explaining how it works under the hood with state machine

[@marketfinds]

Excellent work, glad you went down into the IL Code. Helps make it clearer what magic is going on.

[@RawCoding]

Glad you liked it!

[@elkhoukhi]

Man I just came across your channel, quality material! I subscribed, Keep up the good work

[@RawCoding]

Thank you, hope you like the rest :)

[@Time_Leak]

Thanks for the clear explanation. It was really helpful to see IL that is responsible for all the magic.

[@RawCoding]

Cheers)

[@Esurnir]

Thank you for clearing up this absolute swamp of complexity that is async await in c#

[@RawCoding]

Thank you for watching))

[@martinrogachevsky5627]

One of the best explanations so far, great examples, thanks a lot! Only one thing didn't let me go through this on the first attempt is when you were explaining what network device is doing with the thread on your 'art', you said that it "frees" the thread. For someone who is not native speaker that sounded a lot like "freeze" the thread and really confused me for some time. So just be aware of these little verbal things but in general very helpful and worth sharing!

[@RawCoding]

Thank you, yeah I’m not a native speaker so might mess up some pronouncements

[@No.School.dk_Colur]

I thought I had an understanding of async/await but I didnt have nearly as much understanding as I have now tysm!

[@MichaelVBrown-h2n]

Awesome video! Just what I was looking for. Also while I was diving into the Task code I had noticed a TaskStatus enum at the top. Immediately I was thinking that there must be some state machine at work happening here. So thanks for confirming that.

[@gotham4u]

Wow, I understood it finally . I was trying to understand async and await keywords for last an hour, but "yield" was not comprehensible. Thanks very much.

[@RawCoding]

Cheers, I have a video about IEnumerable and yield you can have a look

[@armandopenaleonett1258]

Thank you I have always had problems understanding this now it's way more clear!

[@RawCoding]

Awesome 👏

[@owiz9212]

Thanks very much Anton! Really simplifies asynchronous processing. Much appreciated!!

[@RawCoding]

Thank you for watching

[@emrealtuntas1319]

After 05:51 i directly clicked like button.

[@RawCoding]

Hehe

[@MetaArcher]

Pretty cool and clear video. One of the best async videos I've seen. Hope next time you do a deep dive to compare Parallelism and Async

[@RawCoding]

Thanks, as I’ve shown in this video it’s pretty much parallel already )

[@sankaralingammuthusamy6142]

It was really superb explanation about async and await. Thanks bro keep up the good work

[@vaya99]

Best explanation for async await 👍, looking for deep dive for .ConfigureAwait() function. Keep it up ... how my computer is expecting it and how to read a code sequence is best part with respect to state sequence explanation.

[@RawCoding]

Glad I could help )

[@BorisMiljkovic]

Finally, a good explanation. Thank you!

[@RawCoding]

Glad you enjoyed it!

[@strange_guid]

Awesome explanation! Please keep up the good work

[@ehsanhadid1260]

Just wow, I want to go back, leave University and just follow you.

[@RawCoding]

Haha don’t do that :P

[@koenfrontatie]

really appreciate your style of teaching! you've helped me lots

[@stevenstone307]

Awesome explanation mate. Funnily enough another thing I learnt in this video is that you can put underscores in big numbers lol

[@RawCoding]

Double whammy!

[@pintileiciprian]

This is great work, man, keep it up!

[@RawCoding]

Cheers ))

[@mrwillis5339]

Useful to hear a concise explanation .

[@RawCoding]

Glad I could help

[@thatguywiththeface9463]

Very detailed and well explained tutorial. Thank you, coding Jesus!

[@RawCoding]

Haha thank you

[@KrishnaList]

Very Nice Explanation Anton It is really Deep Dive

[@RawCoding]

Thanks )

[@ldohlj1]

Wow! Great analogy and great explanation. Thank you

[@RawCoding]

Thank you for watching

[@alexplom5958]

Absolutely phenomenal video

[@RawCoding]

Cheers)

[@AC-fs2rl]

This is the thing I was looking for, thank you

[@RawCoding]

Glad I could help!

[@Hypermommy]

Thank you for this very clear explanation of a sometimes confusing concept.

[@RawCoding]

Thank you for watching

[@emmanuelmotsi]

Such a great explanation. Learn a lot from the DEEP DIVE! Thanks!

[@mkowalski2708]

Just top notch content lately, much appreciated 😁

[@RawCoding]

Thank you ))

[@BryantCobarrubias]

You're a very good teacher.

[@RawCoding]

Thank you

[@iedi3]

very impressive quality, and the relaxed atmosphere just perfect for some cigarettes and a beer (even though i stopped both), plus a reggae music in the background

[@kasra7885]

You left no questions. And a good rhythm

[@RawCoding]

That’s what we like :D

[@BradenJohnYoung]

Finally, a good freaking explanation. Thank you!

[@martinnicolas1399]

Finally, I understand what is happening! Thanks

[@RawCoding]

That is awesome

[@tylergoffinet1085]

Great personifications and IL code walkthroughs! Thanks!

[@RawCoding]

Cheers

[@abhirammadhu2973]

You didn't add sugar😒 BTW, this is the best video explaining async/await in C#. You're right. All other video just simply explains how to implement asynchronous program rather than explaining what exactly happens under the hood.

[@RawCoding]

thank you

[@DynamicalisBlue]

Thanks this is great. I couldn’t sleep without knowing. I’ve always just used it but when I heard about JS Event Loop I was like “C# definitely doesn’t have an event loop right?” but I needed do confirmation. One thing I’m still a bit confused about is that since the tasks can be completed from any thread, how is it I’m able to safely use other objects without running into concurrency issues? For example, if I had two separate Async functions that waited on some network request but upon completion, they both write to a shared data container. I’ve somehow never encountered an issue with this but I’m confused how as if two threads try to write to the same data, it should lead to issues.

[@rowanlidbury]

How have I not found you before.? You need to investigate why you don't show up cos this is gold.

[@RawCoding]

Thank you)

[@onnuttig]

Finally just a simple example of how this shit works, thanks man, instant sub

[@RawCoding]

Glad you like it )

[@Skillamu]

Very good explanation and demonstration. Great video!!

[@loam]

23:36 Second second, heh, nice language metamorphosis, I noticed that thing myself couple weeks ago while ruminating in English, and now It pop ups in the video)

[@RawCoding]

hehe )

[@muxa000]

Wow, this is an awesome explanation!

[@RawCoding]

Cheers

[@tomaszwitkowski9545]

I am in the fifth minute and I got understood it more than I had understood after the classes

[@RawCoding]

Hope you find the rest just as useful)

[@amitagrawal4660]

Very nicely explained 👏

[@RawCoding]

Thank you

[@FroboDaggins]

Hi, what is this .Dump() command? Is this something you wrote yourself or a NuGet package or the program itself? It doesn't seem to be a thing using C# on Visual Studio

[@RawCoding]

it's a method provided by LinqPad, it's a fancy Console Writeline

[@תהילהאהרונוביץ]

you just earned my subscription, great respect for you! 🙏

[@sushil1200]

Very nice explanation!

[@RawCoding]

Thank you

[@arunkutube]

love it, thanks for explaining using ILSpy, it makes things clear.

[@RawCoding]

Glad you like it

[@sreekanthbharatham7577]

Simple and very useful explanation of context switching. Never seen anyone put it together like this. For a long time I was aware the await takes control back to caller making it do other stuff. But never could grasp how potentially another thread picks up the context to continue from where it left off. That realization and looking at different thread ids in different blocks made a world of difference in my understanding. Simply outstanding !! Thank you

[@RawCoding]

Glad I could help:)

[@abdurrahmankhan8680]

Great Job. What a brilliant deep dive.

[@StevenBloomfield]

Always wondered what all the MoveNext calls were in aggregate exception stack traces. I see now where they come from. Thanks!

[@RawCoding]

Glad I could help

[@tarlanismailov5228]

It's clear when you talk about IO-bound operations because that operation can be completed out of the current CPU and there's no point to wait until it's done and additional threads aren't needed. But what about CPU-bound operations? If asynchronous programming implies 1 execution thread, then how CPU-bound operation can be executed without blocking this 1 thread that we have?

[@RawCoding]

Async implies the work will be completed somewhere else, concurrently or parallel you don’t know. Handing off a task to a network card in io bound, is the same as handing off a task to a cpu processor in cpu bound.

[@tarlanismailov5228]

@@RawCoding so based on the above, for example, Task.Delay() operation which is IO-bound will be executed out of our isolated execution environment (I made conclusion that it is isolated) and no additional threads will be added, right?

[@RawCoding]

You won’t know if a thread was added or no

[@tarlanismailov5228]

@@RawCoding I mean within our application

[@RawCoding]

@@tarlanismailov5228 it highly depends and varies from situation to situation. But you won't know.

[@ClassicRollPlayer]

i dont understand what the for loop at 9:44 is demonstrating ... can anyone explain? If make that too long the thread never changes... if I remove it altogether, the threads do change on #5. Thanks!

[@RawCoding]

It’s simulating a busy cpu, if you make it too long it might take a while to get through.

[@ClassicRollPlayer]

@@RawCoding thank you!

[@johndoe3181]

Thanks a lot!! You deserve more viewers!

[@RawCoding]

Thank you

[@ДанекКиллер]

Bro really good explanation, thank you!

[@abuzeromohammed3386]

You hit important topics thanks

[@RawCoding]

Thank you )

[@gianmarcote]

Subscribed just by watching this video!

[@RawCoding]

awesome :) glad you like it

[@gianmarcote]

@@RawCoding Just to clarify, the most obvious gain from this is that we are freeing up the thread while the operation is ongoing, right? And then when the operation completes the state machine will kick in and transfer control to the code after the await?

[@RawCoding]

Yes

[@davidhainovitz2838]

Hi great explanation: Just would like a clarification: I'm referring to around 10:00 when you reduce the looping time. When its long the original thread still exists so the rest of the program uses it till the end even though the task uses a different thread as compared to when the loop is shorter so its released before the task completes and a different thread completes the program. Is this a correct understanding? Thanx

[@stivio00]

Awesome! really nice explained.

[@RawCoding]

Thank you)

[@qwerty5689]

Thanks for your vids mate. Really helpful! Keep it up :)

[@RawCoding]

Thanks )

[@drillerboyyt4027]

I am so happy I found his channel.