29. Multithreading and Concurrency in Java: Part1 | Threads, Process and their Memory Model in depth

[@chiveshupneja1593]

Such a crystal clear explanation of core concepts, I don't think no body explains so well even in highly paid courses. Thanks Shreyansh!!

[@ConceptandCoding]

Thanks 🙏

[@iqrarahmad59]

those who sell high paid course are the ones who got laid off or quid due to lack of real knowledge

[@DurgaShiva7574]

what a lecture, what a learning, awesome, as a professional, i didn't knew 10% of what u taught today, kudos to you

[@ConceptandCoding]

thanks

[@NagoorShaik-nx9qm]

Can't stop commenting after listening to this lecture. The best explanation to understand how process and thread works in the background. Thank you Shreyansh!!! Kudo to the level granularity.

[@PlugNPlay960]

I just finished watching this video and I wanted to take a moment to commend you on the fantastic job you did. Your clear explanations and engaging presentation made complex concepts easy to understand. The way you break down the information is amazing. It's evident that you put a lot of effort into your content, and it truly shows. Thank you for creating such valuable and insightful videos that make learning enjoyable!

[@knpragash]

You have the GIFT in Teaching !

[@saswatsenapati7870]

The difference here is the blend of java concepts + core cs concepts. Very rares you find some one teaching a language actually mapping with its actual cs core concepts.

[@MAHALAKSHMIVEERARAJ]

Great explanations and main thing is that you are teaching everything based on your real industry experiences. Great learning experience! Heartful Thanks to you!

[@ratansarkar7444]

How someone can give indept knowledge for free..I'm glade to have you as java trainer

[@ConceptandCoding]

happy learning

[@stepswithvishnu2924]

Worth to have your channel's membership. Nicely explained.

[@ConceptandCoding]

🙏

[@SahithiMangalapalli]

It's absolutely clear and such a great learning, I can't thank you enough for sharing such valuable knowledge

[@ConceptandCoding]

thanks

[@fa1con989]

Eagerly waiting for the spring playlist

[@AkashGupta-jb7zj]

One of the Best Vedios of Explaining the working of Threads in Java, totally loved it, it also cleared my doubt regarding the CPU cores and the Thread allocation to them, how they work in parallel and with context switching. Thank You So Much and Kudos to You!!

[@ConceptandCoding]

thanks

[@afterfridaystories]

Just Loved It ! 1 complete / all 10 Multithreading videos. This weekend I will complete all 10 !

[@imrohan97]

God-level concepts.Thanks for such valuable content.

[@ConceptandCoding]

thanks

[@chhitijsrivastava793]

Really nice lecture, you made my day. I was literally searching for a Java course online and your course series is truly awesome. Thanks for your effort; such high-quality resources are rarely found almost free anywhere else. Thanks, Shreyansh ❣

[@ConceptandCoding]

Glad to hear that

[@Rameez-Raja]

you made my day.. Thanks for the crystal clear explanation in simple terms ❤🎉

[@sujeetbadnale9441]

God Bless You Brother😊. It was indepth and in one flow. We kind of learn in peaces and we forget, but tought us in peaces and also combined them in a single flow, which is more beautiful. You are a great god gifted teacher, carry on. Keep Sharing. Be Blessed and Be Blessing for others as you already are 😊 One small request though, the last part where the actual execution that happens on CPU was bit unclear to me, if possible could be please create a seperate video which explains that in details?

[@ConceptandCoding]

Thanks, sure will cover

[@drissaitkassimusic]

You deserve more than million subs 👍👍👍👍👍

[@adityagupta375]

It's amazing the details shared in the video, please let us know where do you get all the knowledge from, the books you read or any kind of other resources. It will be very helpful for self-study and upskilling.

[@ConceptandCoding]

thanks. Many with experience in would say Aditya. Its been 8yrs and still working with Java tech stack only

[@rajneeshyadav3444]

I believe even the creator of Java couldn't explain it better than you did.

[@pulkitxd]

@Shrayansh bhai, Kindly enable download on member videos. Some of us have subscribed to membership, download & watch videos offline, especially I use my commute time to watch videos offline.

[@ConceptandCoding]

ack, will do buddy

[@Sushil2874]

Wooo...Take a bow.... Such a great explanation..🙌 Really looking forward for upcoming ones for this topic. Also, show the things with code execution wherever it is possible, which you always does so. Thank you!

[@ConceptandCoding]

Sure, thanks 🙏

[@pleasantdayNwisdom]

VIDEO 3 My Motive for commenting: Watching all videos of sir/bhaiya , to get his personal guidance and referals for sde job . My Feeling : Amazing to learn from someone in big position in paypal company Want to be under ur guidance and chatrachaaya Thankyou Shrayansh sir/bhaiya

[@mithunvasisht3176]

@Shreyansh Great content. One thing I wanted to know is where is Code Segment present? In the ROM/EPROM? What about extra segment ? In the RAM? This needs to be known. Probably a small wrapper class on CPU architecture and where different segments are located shall help understand multithreading better

[@amalamal3312]

wow .just amazing

[@yogendrasingh-nz3pw]

Thanks a lot for this wonderful knowledge sharing. Can someone please tell where is the remaining videos for multithreading part 2

[@vaibhavjain1124]

Truely very great content man!! Just one suggestion, is it possible that when you research for these videos you can mark the sources too any books articles etc. And for this thread series any suggestion for any good resources explaining with this level of deepness or any sources you used can you link them.

[@zaheerabass7955]

Point to point brings very much clearity. Thank You

[@ConceptandCoding]

thanks

[@shoaibakhtar9194]

Hello Shreyansh, great content like always. One request:- I couldn't find the notes of multithreading lectures in the community post. Could you please post it there?

[@siddhantprakash.]

maza aaya kaafi din baad kuch padh ke. #Day4 of 7Days of java

[@keshavdeosharma7222]

Very nice explaination. Thank you Sir

[@nikhilkumar3124]

Good videos. Cleared lot of doubts.

[@ConceptandCoding]

Thanks

[@saurbhbansal7408]

Hi very useful video, but I guess you didn't make a playlist for this. It's a little difficult to find the next part's video in this sequence.

[@AkshayAgarwalCoding]

Hi Shrayansh, Great, video once again but where is part 2?

[@AmanKumarSamal]

Thank you for such a nice explanation!

[@nishantkumar6116]

Nice Explanation...please create videos on Aspect Oriented Programming, I've got several question from AOP and spring AOP in my recent interviews

[@ConceptandCoding]

ack

[@rajanikushwah1414]

Following java Playlist and explanation 👌. When can we expect spring Playlist ?

[@ConceptandCoding]

After Java, Java thodi hi bachi hai bas

[@piyushjainwork01]

Also Can you please brief me about how the metaspace came in picture and in which memory it will get allocated. from instance of JVM or the central JVM or The natice memory?

[@asharya5311]

@Shreyansh Jain Thank you for the informative lectures, recently took the membership, but not able to find multithreading notes link in member community post. Please help.

[@ashutoshsinghyadav5412]

faad diya Nice investment by me on myself

[@jayendrasingh9260]

One of the best 👍

[@ConceptandCoding]

Thanks

[@nirajosh]

Hey Shreyansh, Any idea about how virtual threads are working ? Is Virtual thread same as a Thread ? if possible, Can you come up with some sort of video which will explain Virtual Thread ?

[@ConceptandCoding]

Hi virtual thread is not same as Thread but they are backward compatible. In our traditional thread, JVM create respective native thread (OS level Kernel thread). so you can say JVM provide us the abstraction, when we say Thread.start(), it actually tells OS to create new native thread. But Virtual thread, introduced in Java19, here JVM takes the responsibility of managing the threads and it creates many virtual thread and map to very less number of native thread. Means Multiple virtual thread can work on single virtual thread. Virtual thread provides backward compatability, i can create a video of it. But i need to install latest JDK for it :) will do it later and create a video. But i know this info will help you in clearing your doubt.

[@car_holic1995]

Bhai itna detail me self study karna ho toh?

[@JaiChandraSekarRK]

brilliant explanation, thoroughly enjoyed it...where can i find part 2 and so on?

[@ConceptandCoding]

check the playlist 30th no video is part 2

[@lakshmanankanthi7158]

Hi sir. Thanks for the clear explanation, just a doubt. What is the difference between JVM heap size and JVM instance heap size? Is there something like global JVM? Thanks

[@garvitjain9933]

Does JIT create all the required threads before running a process? Refer to the video at 32:30. This seems counter intutive

[@mehnaazmohiuddin]

you are doing a great job. Keep it up

[@mehnaazmohiuddin]

one small thing that took me to other articles was what register is storing .. seems like its saving the operator , operands. there are multiple registers from what i have come to understand .. i guess atleast 3 to store operator , operators and accumulator. to come back to do what it was doing. Simply great work though . This must be taking so much of your time! good job again

[@kritisingh1347]

thanks shreyansh

[@adhyanneekhra4853]

When I run Java -Xms256m -Xmx2g Test What will be the total JVM heap memory allocated. How much each process JVM instance will get if I have 2 process running. And how it will be decided?

[@krishnendughosh2368]

22:15 shouldnt we call this Interpreted bytecode instead of compiled bytecode? Btw I have faced this issue of writing junits for multithreading and also debugging issues. We used webclient for rest call and it was customized heavily, so a big chunk of code was not under any junits. It reduced our ovrall test coverage but mejority of use were not able to write test for it, not even the developer who wrote the class at the first place. Can you please add one video to address these two challenges you mentione?

[@tomorrowcut]

Hi Shrayansh, Can you please help with an answer? Compilation (javac Test.java): generates bytecode that can be executed by JVM. Execution (java Test): at this point, JVM starts the new Process, here Test is the class that has the "public static void main(String args])" method. In your notes above, it is stated that JVM starts a process. and later you said that once the process is created, a new JVM instance is created. Are there two JVM instances, one which creates a process and the other one that is being created once the process is created?

[@coolone5561]

Edited: When you run "java Program", OS launches a process called JVM process. JVM initialises resources like memory and stuff like loading byte code into memory. And then it looks for main thread in the code and starts running that thread. Yes, When you run a program, the JVM process is created and the threads in your program run inside it.

[@gauravraj2604]

Really liking your explanation. 1 doubt I had. Where exactly we tell how much heap memory to be allocated while creating a process?

[@gauravraj2604]

sorry got it. at the time of process execution itself we specify memory. e.g java . However, if I don't specify the heap memory size at the time of process execution, how much heap memory will be allocated to this process then?

[@ConceptandCoding]

@@gauravraj2604 yes

[@gauravraj2604]

@@ConceptandCoding However, if I don't specify the heap memory size at the time of process execution, how much heap memory will be allocated to this process then?

[@SaiKumarVukkum]

in Register section reshuffling the instructions means...please clarify

[@Krishna-iu4zp]

context swithing is b/w processes or b/w thread or both ? (47:08)

[@ManjeetKaur-y1y]

@Shreyansh Great Explained but where is part 2 video?

[@ConceptandCoding]

already uploaded buddy 7-8 parts are there all uploaded

[@Ashish-hr3zn]

Bit a MIxture of Compiler , Os , Computer Architechture ,nice video

[@aashiarora3150]

@Concept_&&_Coding How does JVM know how many threads it requires to execute a program?

[@ruthvikreddy1625]

why is thread the smallest sequence of instruction? What does smallest here refer to?

[@theunusual4566]

Thank you.

[@kaushikghosh8406]

What algorithm does this context switching follow? FIFO? Shortest job? Round robin?

[@ConceptandCoding]

its depends on scheduler to scheduler, various algo like priority based scheduling and there is one more time-sharing scheduling algo is used. but i need to check more on that.

[@abc-ym4zs]

Sir i want your suggestion i not able to understand the reactjs and backend technologies 😢 and i am not able to improve my problem solving skills i am in third year loosing interest in studies can u tell me how to get back to track

[@sargamgoyal4161]

Please make video on lambda functions also.

[@ConceptandCoding]

It's already there, pls check previous videos in Java playlist buddy

[@piyushjainwork01]

I am struck 35:00 second where i am not able to understand who will start the main thread?

[@kamalrai286]

If there is one CPU and one register so how is it possible for thread having their individual registers

[@Randomvideo2610]

what happens for api call it create separates process for each api call and allocates heap memory.

[@jayendrasingh9260]

Each api calls his handle by spring internal threads

[@umairalvi7382]

Why does it never happen that multiple threads execute the same statement multiple times how is it distributed among threads??

[@ankitakumari5936]

Is there any other medium to join membership, as I am facing issue while payment

[@ConceptandCoding]

you can check Udemy or Udemy Business.

[@LaptopBackup-bo6kp]

Is data segment alias for metaspace?

[@car_holic1995]

If coder dont create threads exclusively..task is completed by only main thread?

[@ConceptandCoding]

Right

[@balakrushnabehera1631]

Hi Shreyansh why doesn't the below code work asproducer and consumer problem's solution import java.util.*; class Producer { Queue queue; Producer(Queue queue){ this.queue= queue; } public void produce(int data) throws Exception{ synchronized(queue){ while(queue.size() == 3){ //waiting for consumer to consume items System.out.println("waiting for consumer to consume items"); wait(); } System.out.println("Added item: " + data); queue.add(data); notify(); } } } class Consumer { Queue queue; Consumer(Queue queue){ this.queue= queue; } public void consume() throws Exception{ synchronized(queue){ while(queue.isEmpty()){ //waiting for producer to add items into queue System.out.println("waiting for producer to add items into queue"); wait(); } System.out.println("Removed: " + queue.poll() + " Current Queue Size is: " + queue.size()); notify(); } } } public class Main{ public static void main(String[] args) throws Exception{ Queue sharedQueue= new PriorityQueue(3); Producer producer= new Producer(sharedQueue); Consumer consumer= new Consumer(sharedQueue); Thread producerThread= new Thread(() -> { try{ for(int i= 0; i { try{ for(int i= 0; i

[@ConceptandCoding]

ack will check buddy

[@soumyaprakashsasmal6770]

I have been thinking my professor made me understood OS very clear during college....I was wrong the whole time

[@nitishchaudhary7777]

Bro, unable to find part 2, is that uploaded/created?

[@ConceptandCoding]

video no 30. is part2

[@sweetygangane4551]

Teaching is good but... This unlocking vdos not giving so much link

[@harshitanand7349]

The Physical Memory in the diagram is RAM, right? Let’s say I have a 8gb RAM system and 600mb are free. If I do - java -Xms1g -Xmx2g Test Will it give OutOfMemoryError ?

[@kent.johnson]

Nice

[@gauravraj2604]

If I don't specify the heap memory size at the time of process execution, how much heap memory will be allocated to this process then?

[@ConceptandCoding]

Default values are used which depends on system configuration and JVM. Generally min geap is 1/64 of total RAM. And Max heap is 1/4. But these values can change depending upon the system. There is a command too, through which you can know how much default heap value is set. I will look for that command and share with you.

[@gauravraj2604]

@@ConceptandCoding thank you for your response . Please do let me know the command.

[@CodeTonics]

how can i download the notes

[@adhyanneekhra4853]

Yeah even I am not able to download Zoho one

[@imrohan97]

A 19:11, how does it get decided that how much Total JVM Heap Memory will be allocated

[@imrohan97]

Also, at 20:30, how much memory is allocated to the code segment, data segment, register, stack, and counter together? Is it different from heap memory?

[@techmind9608]

Hi brother, i have bought membership but still unable to watch videos, there is note that says, you need membership, but i am already member, i bought it a day ago

[@ConceptandCoding]

kindly check the membership level pls

[@atulvidyarthi9952]

Where is metaspace in this?

[@karmicveda9648]

🙌

[@car_holic1995]

Please include coding also bhai..

[@ConceptandCoding]

I will, this is fundamental video, what is process and thread. Thread creation will go next with coding buddy

[@rishiraj2548]

🤘

[@Shadabkhan-tz7uv]

Who is bro?💀🙌