demonstrate jdk cgroup bug - incl mem

s50600822 · Feb 29, 2024 · e9f0ba9 · e9f0ba9
1 parent 4cf98f8
commit e9f0ba9
Show file tree

Hide file tree

Showing 4 changed files with 13 additions and 2 deletions.
diff --git a/vs/java/cgroup/CgroupConfigPrinter.java b/vs/java/cgroup/CgroupConfigPrinter.java
@@ -1,3 +1,6 @@
+import java.lang.management.ManagementFactory;
+import com.sun.management.OperatingSystemMXBean;
+
 public class CgroupConfigPrinter {
     public static void main(String[] args) {
         int availableProcessors = Runtime.getRuntime().availableProcessors();
@@ -14,5 +17,13 @@ public static void main(String[] args) {
         System.out.println("Available Memory (Total): " + totalMemoryMB + " MB");
         System.out.println("Available Memory (Free): " + freeMemoryMB + " MB");
         System.out.println("Maximum Memory (Allocated): " + maxMemoryMB + " MB");
+
+        OperatingSystemMXBean osBean = (com.sun.management.OperatingSystemMXBean) ManagementFactory.getOperatingSystemMXBean();
+
+        // deprecated in favor of getTotalMemorySize(), however new method is not avail on JDK8
+        // keeps this so we can test against 8 and above
+        long totalSystemMemoryBytes = osBean.getTotalPhysicalMemorySize();
+        long totalSystemMemoryMB = totalSystemMemoryBytes / (1024 * 1024);
+        System.out.println("Total System Memory: " + totalSystemMemoryMB + " MB");
     }
 }
diff --git a/vs/java/cgroup/application.jar b/vs/java/cgroup/application.jar
diff --git a/vs/java/cgroup/runWithDocker.sh b/vs/java/cgroup/runWithDocker.sh
@@ -1 +1 @@
-docker run --rm --cpus=2 --memory=256m --name jvm_cgroup_demo_openjdk21 -v .:/app openjdk:21  java -Xmx256m -Xms256m  -jar /app/application.jar
+docker run --rm --cpus=2 --memory=512m --name jvm_cgroup_demo_openjdk21 -v .:/app openjdk:21  java -Xmx256m -Xms256m  -jar /app/application.jar
diff --git a/vs/java/cgroup/runWithDockerJ8.sh b/vs/java/cgroup/runWithDockerJ8.sh
@@ -1,2 +1,2 @@
 ## show that cgroup for CPU lim isn't respected
-docker run --rm --cpus=2 --memory=256m --name jvm_cgroup_demo_openjdk8 -v .:/app openjdk:8  java -Xmx256m -Xms256m  -jar /app/application.jar
+docker run --rm --cpus=2 --memory=512m --name jvm_cgroup_demo_openjdk8 -v .:/app openjdk:8  java -Xmx256m -Xms256m  -jar /app/application.jar
Original file line number	Diff line number	Diff line change
		@@ -1 +1 @@
		docker run --rm --cpus=2 --memory=256m --name jvm_cgroup_demo_openjdk21 -v .:/app openjdk:21 java -Xmx256m -Xms256m -jar /app/application.jar
		docker run --rm --cpus=2 --memory=512m --name jvm_cgroup_demo_openjdk21 -v .:/app openjdk:21 java -Xmx256m -Xms256m -jar /app/application.jar