It's been a while since your last video! please share your knowledge again, you have a very good way of explanation. you might as well do udemy courses or create a paid courses on your youtube channel

Hey the channel is amazing! Just wanted to know when will you start uploading new videos?

Hello Defog Tech Thanks for the clear and candid explanation. PFB, one of the formulae for ideal number of threads. #of Threads

Simple explanation ! Golden stuff! Thanks

Wow... A very complex topic in a very simple way...Love you man.

This word would not enough but please take it as appreciation far beyond : AWESOME

The best ever video on thread. Looking forward to more videos. 👍

what an explanation brother, really good, clear and very helpful .. thanks a ton!!

Your explanations are amazing. I believe, you ARE the gift given me for all the efforts I made before by learning Java and Spring :D . Thank you a lot!

This video has the clearest explanations around this topic from what I have ever watched!

These really are excellent videos. I've been a software engineer for almost a decade now, and while I more or less understand concurrency theory for distributed systems (well, as much as anyone CAN understand it :) ), I will admit that I never really bothered learning much about low-to-mid-level multithreading. These videos are easy to follow, well presented, and provide a lot of "bang for your buck" time-wise.

one of the beat video tutorial in short time in easy way

best explanation i have come across so far on threadpool and its dilema. I spent last one week reading windows via c trying to understand what you explained here in under 15 mins. Thanks a lot.

Thank very good explained!

Very nice explanation, pls keep sharing such exclusive knowledge. Thank you.. Awaiting for more such videos. Thanks once again. 👍

amazing, this is such a good explanation, very simple and clear. No wasted time. Thank you!!!

Amazingly explained, wonderful job

All your videos are very informative and insightful. Wish you'd make more such videos!

Very well presented and explained. Keep up the good work!

All my respect Sir! Plz continue :)

Wow, best explanation ever, Thank you

You are a gifted teacher!

Awesome video!!! Enlightening

excellent video. I was searching from long time

Amzing content. Provides great clarity. Please do a series on the design patterns. And object oriented design like designing a parking lot.

Please continue posting videos. Not everyone can explain complex concepts in a simple manner.

Perfect !!!

Sir, that's another Masterpiece from you...Thanks !

Wow! Amazing explanation.

Really really helpful video!!!

Thank you very much for the video 😁

Great explanatory video 👍👍

learned a lot, useful to tlak about these things for any lowlevel design discussion, staff eng level experience gained!!!

Excellent - so much relevant content in less than 15 mins.

@akashshirale1927

3 жыл бұрын

u r that famous guy on leetcode

Wow, thanks a lot for making such informative videos

Perfect!!

Thanks for such a nice explanation

Please start making videos again. Your videos are very informative and easily understandable. Hope to see you soon making videos.

Nicely explained, thanks for the video 👍👍

Excellent explanation, loved the nuances and detailing

Tremendously awsum explanation.

perfect ...thank you

Great explanation

Really nice explanation !!

Done thanks CPU bound tasks (no blocking) pool size is number of cores 7:30 IO bound task diagram 11:30 Formula for number of cores wait time is how much time the thread is in wait state, and cpu time is how much time the thread spends executing For example, if the task executes for 1 second and 0.5 seconds of that is blocked on IO, then ideal thread count will be if we have 1 core 1(1+ (0.5/0.5)) = 2 threads What if the task blocks longer? Say total execution time 1 second but 0.8 blocked Ideal thread count = 1*(1+(0.8/0.2)) = 5

13:31 "L1/L2 etc need to be flushed during a thread switch", while it's architecture specific this is only needed for switching between processes, however if switching between different threads in the same process they share the same address space, so no flushing is needed (ignoring relevant fences). Also it the L2 cache is shared between multiple cores and wouldn't be flushed however the TLB and L1 potentially are.

Nicely explained

Pls continue uploading new videos.. The channel is idle, you should continue.. it is really amazing..

Excellent 👌 explanation. Please do more videos on java concurrency. Also my suggestion is it would be great if you create videos which covers java concurrency book with your animation and explanation Thanks again

Now I understand it :)

One of the best explanations for thread pooling I have seen so far which many have failed to do. It would be great if you can extend the discussion on how hyperthreading works along with thread pools.

@DefogTech

4 жыл бұрын

Good idea... I want to explore hyperthreading concept, might do separate video on it

Thank you

Your videos are short and sweet. If you have some time to spare with us, I expect rx Java from you. Thanks.

You are one of the best tech youtubers. Please come back to youtube.

This advice is true if it assumes that there are no other threads running on the computer computer but of course there are thousands of threads running typically or at least hundred and so the more threads you allocate the more the scheduler gives time to your application. In addition to increasing the nice number / priority

@DefogTech

9 ай бұрын

Agreed. Though its more true during development and testing where you application is running with many others. For production though, even with containers typically the application has fixed set if resources assigned and the sharing is minimal

Impressive

We would love to have live Q&A if possible

Hi Defog Tech , thanks for the tutorials ! Could you make videos (even better if a playlist of tutorials) about advanced topics and real-life examples about Maven ? For example, releasing of projects with complex versioning, git/jenkins/artifactory integration etc... Any intermediate - advanced topics would be very much appreciated. Online tutorials nowadays about maven only cover very basic concepts and they are all the same (e.g. dependencies ... everyone knows about it).

For people who don't have patience: The answer is: it depends on whether the task is CPU intensive or IO intesive. If it's CPU intensive, it is = number of cores, if it's IO bound, it is = depends on how much time the IO intensive task is eating on CPU. Usually much more than the number of cores.

Waiting for new videos from your channel

Awesome explanation, just a view you may add memory usage of the task as an important parameter in the formula because it is one of the essential factor which restrict us in number of threads. Also you may add some explanation like what will happen if you try to start 1000 threads but fixed number of parallel threads are only 10. Mean will CPU keep them in memory or what would be the scenario. Other than this i felt its a very good explanation. :)

Sir, could you please make video about differences between embeded server and standalone server at performances aspect in Java ecosystem ? I love the learning more deep about that and how it takes benefit for microservice architecture

Thanks for the Video. Just curious about scenario for I/O tasks scenario if the I/O is non-blocking IO(In above Video it is assumed I/O is blocking I/O). It just appears in that case increasing the size of threadpool may not give any benefit as the thread will need not to wait for I/O in non-blocking scenario and can take up another task in meantime and even one thread (in single core machine scenario ) may suffice .

Hello Sir, your explanations r very pin point, please upload some Design patterns best practices and application level Exception hanndlings . SSL usage rest security like basic, oath , encryption realtime usage in microservices and normal projects

Super video! I applauded for ₹40.00 👏

Wow...

An alternative formula for the number of threads would also be: N = CORES * (ALL_TIME / CPU_TIME), where ALL_TIME is just IO_TIME + CPU_TIME.

@johnathanrice3569

9 ай бұрын

All time is IO time plus CPU time plus other thread time. The more thread you run the more time you’ll get scheduled for each threads overall. Instead of 1/1000 you’ll get 100/1100 all things else considered equal

I always got confused when I was asked this question in interviews........Thanks for elaborating it........Excellent explanation...

Confused ... but i know you are explanations are good

can you make videos how threads contribute to L1/L2/L3 cache memory. give some practical scenarios.. thanks for this nice videos..

I don't know if you realize it but you're content is great. I hope more poeple press the applaud button that supports you monetarily. Please continue making videos.

Thanks for amazing explanation, pls upload videos for spring

Is there an overheard of creating a threadpool rather than using the java system threads using completablefutures?

Best explanation I have heard. But how do I estimate the CPU time and Wait time accurately ?

Nice Video....Can you pls explain the Thread/Core management in Cloud environment where core size can be in millicores....

Please do more videos

Please upload more videos

Great explanation! What if we have multiple threadpool instead of just one single threadpool in an application, can each still have same coreThreadSize?

Hi I have been following your videos since few years now, and have started reading JCIP book for further clarity. Ny question is, Do programmers of bigdata field too need to understand concurrency?? Or is it handled by the latest frameworks like spark storm etc

@DefogTech

3 жыл бұрын

For BigData processing I dont think understanding of Java concurrency is necessary. You might need to understand concurrency in general at data flow level, but not in-depth like these tutorials.

Where did u go Defog Tech? please come back

What is consistent hashing?

Why did you stop making videos, these are so helpful..

Great explanation. I had a question - what happens if a method has both IO and CPU bound operations? Does IO bound operation take precedence over CPU bound operation?

@DefogTech

Жыл бұрын

I didnt fully understand. If method has sequential code it will be executed in that sequence irrespective of whether its IO or CPU bound. At a kernel level too, threads are given equal opportunity to run and I dont think IO vs CPU is a scheduling factor.

Wondering how to find out the wait time and CPU time 🤔 Maybe jstack can help...not sure

@Defog Tech what happened man? you are not posting any more videos .

Wow .. great respect for your way of teaching and knowledge...Do you have any courses in Udemy.. I’ll buy it...

@DefogTech

4 жыл бұрын

No courses as of now Uday, might start KZread memberships if there is enough interest

I think you should appear sometimes in videos person talk to your students. It will surely help your channel. It's been a year You have not uploaded any videos. I think you have potential to become next java brains. I hope you start uploading as project reactor is maturing and I don't see anybody else who could teach devs write non blocking code. Or you can jump into gRPC. Thank you for for all these efforts. Start coming live turn on the super chats. Join button won't help it is more of commitment and you know commitments.

Extremely good explanation. Let's say I have 2 cores and I create a thread pool of size 2. That means I have the main thread plus 2 child threads = 3 threads total, right? Why isn't the main thread being taken into account in your calculations? Thanks

@DefogTech

3 жыл бұрын

AFAIK, in webservers in addition to main-thread there are lot of other threads (eg: GC thread). Have used only request accepting/processing threads in this example to keep it simple.

How to calculate the wait time and CPU time of a task ?

It has been a while since we got new tutorial from you. Hope you are doing fine.

Can you please add a video for it?

writing data into a file is a CPU IO operation right?

Hi, I am very new to the java concurrent programming. Your playlist have helped me a lot in understanding the basics. Thank you so much for giving such a simple explanation. I have a doubt regarding thread count calculation, suppose there is a system which need to get some large number of customer data of from DB/System (ie IO operation) and want to process, validate (ie CPU intense operation) data of each user and update the validation status back to DB/System (ie IO operation). How should I calculate/ design the thread count? Please correct me if I am wrong about the scenario. Thanks in advance.

@DefogTech

4 жыл бұрын

Good question. It depends on how much time it takes for read IO operation to complete which will define rate of incoming tasks and how much time the CPU intensive operation takes which will define how many of these tasks can you run in parallel (at a time). So if CPU intensive task takes 10ms, then you can have max N of such tasks, where N = Number of CPU cores.

@sreejiths8159

4 жыл бұрын

@@DefogTech Got it . That make sense.Thank you for the explanation.

For IO bound tasks, we can have more threads in the pool for a fixed number of CPU cores. In real life scenarios, have you performed trial and error to arrive at the ideal count of threads, by observing the average wait time for such tasks?

Sir, what about file operation tasks such as PDF/Excel report creation, is it a CPU intensive or IO-intensive? My guess would be IO intensive

@DefogTech

4 жыл бұрын

creating the format in-memory would be CPU intensive, and post that writing to the disk would be IO

Let's suppose I have hit the post api and saved the data in db via jpa ... Now I am using back button and resubmitting the request again 3 time and each times data is pushed in db ..and I don't want to insert resubmitted data in the table , could you please tell me how we can achieve this TIA 😊

@DefogTech

3 жыл бұрын

you should use an idempotency key which is hash of the data being inserted, and set unique constraint within DB itself. this should not be handled at code level IMO

@pramodjalindra5414

3 жыл бұрын

@@DefogTech thanks let me try 😊😊

What is database sharding?

@DefogTech

4 жыл бұрын

I have a series coming up about NoSQL which will cover sharding/partitioning

I have one confusion: how many types of thread are there ? I know there are threads related to cpu, then there are probably os threads, and then there are java threads. How do they relate to one another ?

@DefogTech

Жыл бұрын

Behind the scenes everything is a thread of same type. Every process, whether its OS utilities or applications or services, work using threads. I am sure there are commands for every OS which lets you find how many threads each process is using. Try that out for various types of applications. There are no threads related to CPU AFAIK.

@updownftw

Жыл бұрын

@@DefogTech Thankyou for your reply Deepak. So when a processor says i9 8 core and 8 threads. That means they are saying 8 things can run parallelly on those 8 cores at at time ?

@DefogTech

Жыл бұрын

@@updownftw yes, correct. 1 thread per core. Note: There is a feature in both Intel and AMD CPUs called SMT which allows 2 threads per core, but even that is not technically concurrent, and its disabled generally due to recent vulnerabilities.

@updownftw

Жыл бұрын

@@DefogTech Ok, thanks Deepak 👍🏽

sir,explan the process,thread,task term with real time examplr.confuse alot. thank u

@sireesham4208

4 жыл бұрын

Process: A process is an instance of a computer program that is being executed. It contains the program code and its current activity. Depending on the operating system (OS), a process may be made up of multiple threads of execution that execute instructions concurrently. Process-based multitasking enables you to run the Java compiler at the same time that you are using a text editor. In employing multiple processes with a single CPU,context switching between various memory context is used. Each process has a complete set of its own variables. Thread: A thread is a basic unit of CPU utilization, consisting of a program counter, a stack, and a set of registers. A thread of execution results from a fork of a computer program into two or more concurrently running tasks. The implementation of threads and processes differs from one operating system to another, but in most cases, a thread is contained inside a process. Multiple threads can exist within the same process and share resources such as memory, while different processes do not share these resources. Example of threads in same process is automatic spell check and automatic saving of a file while writing. Threads are basically processes that run in the same memory context. Threads may share the same data while execution. Thread Diagram i.e. single thread vs multiple threads Task: A task is a set of program instructions that are loaded in memory.

Looks like this is your last uploaded video on this channel. Why you have stopped creating these awesome tech videos? Is everything alright bro?