In this session, we will learn about the various concepts of concurrency which is applicable to both Scala/Java since Scala concurrency model is built on top of java concurrency model.

1. Presented By: Bhavya Verma
Concurrency in Scala

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3. Agenda
01 Parallelism vs Concurrency
02
04
05
03
ExecutorService
Type of pools
How ForkJoinPool works
Volatile vs AtomicInteger

4. Parallelism
vs
Concurrency

5. Parallelism
● Parallelism is about doing a lot of
things at once.
● Parallelism requires at least 2 cores
in the processor.

6. Concurrency
● Concurrency is about dealing with a lot
of things at once.
● Concurrency occurs when there is a
single core on the processor.

7. ExecutorService

8. ExecutorService
def main(args: Array[String]) = {
val thread = new Task
thread.start()
println("Thread " + Thread.currentThread().getName() + " is running.")
}
class Task extends Thread {
override def run(): Unit = {
println("Thread " + Thread.currentThread().getName() + " is running.")
}
}

9. ExecutorService

10. ExecutorService
def main(args: Array[String]): Unit = {
for(_ <- 1 to 10) {
val thread = new Task
thread.start()
}
println("Thread " + Thread.currentThread().getName() + " is running.")
}
class Task extends Thread {
override def run(): Unit = {
println("Thread " + Thread.currentThread().getName() + " is running.")
}
}

11. ExecutorService

12. ExecutorService

13. ExecutorService

14. ExecutorService

15. Type of pools

16. Type of pools
● FixedThreadPool
● CachedThreadPool
● ScheduledThreadPool
● SingleThreadedExecutor

17. FixedThreadPool

18. CachedThreadPool

19. ScheduledThreadPool

20. SingleThreadExecutor

21. How ForkJoinPool
works

22. ForkJoinPool

23. Per thread queueing

24. Work Stealing

25. Volatile
vs
AtomicInteger

26. Volatile

27. Volatile

28. Volatile

29. Volatile

30. Atomic Integer

31. Atomic Integer

32. Atomic Integer

33. Atomic Integer

34. Thank You !