20241219 CPU , IO bound 학습

Author: LimZida

src/main/java/io/concurrency/chapter01/exam03/CPUBoundExample.java

@@ -6,7 +6,13 @@
 import java.util.concurrent.ExecutorService;
 import java.util.concurrent.Executors;
 import java.util.concurrent.Future;
-
+/*
+* CPU Bound - 영상처리, AI 작업 관련
+*
+* 멀티코어의 병렬성을 이용한다.
+*
+* CPU 수 >= 스레드 개수
+* */
 public class CPUBoundExample {
     public static void main(String[] args) throws InterruptedException {
 

src/main/java/io/concurrency/chapter01/exam03/IOBoundExample.java

@@ -5,10 +5,16 @@
 import java.nio.file.Path;
 import java.util.concurrent.ExecutorService;
 import java.util.concurrent.Executors;
-
+/*
+* IO Bound - DB작업이나 파일 읽는 작업
+*
+* 멀티스레드의 동시성을 이용한다.
+*
+* CPU 수 < 스레드 개수
+* */
 public class IOBoundExample {
     public static void main(String[] args) {
-        int numThreads = Runtime.getRuntime().availableProcessors() / 2;
+        int numThreads = Runtime.getRuntime().availableProcessors() * 2;
         ExecutorService executorService = Executors.newFixedThreadPool(numThreads);
 
         for (int i = 0; i < numThreads; i++) {
@@ -17,7 +23,7 @@ public static void main(String[] args) {
 
                     // IO 가 집중 되는 작업
                     for (int j = 0; j < 5; j++) {
-                        Files.readAllLines(Path.of("D:\\lecture\\Java-Concurrency-Programming\\Java-Concurrency-Programming\\src\\chapter01\\exam03\\sample.txt"));
+                        Files.readAllLines(Path.of("C:\\workspace\\java-concurrency-study\\src\\main\\java\\io\\concurrency\\chapter01\\exam03\\sample.txt"));
                         System.out.println("스레드: " + Thread.currentThread().getName() +", " +j); // IO Bound 일때 ContextSwitching 이 일어난다
                     }
 

src/main/java/io/concurrency/chapter01/exam03/sample.txt

@@ -0,0 +1 @@
+why so happywhy so happywhy so happywhy so happywhy so happywhy so happywhy so happywhy so happywhy so happywhy so happywhy so happywhy so happywhy so happywhy so happywhy so happywhy so happywhy so happy