[IGNITE-13306] CpuLoad metric return -1 under Java 11

• Type: Bug
• Status: Resolved
• Priority: Major
• Resolution: Fixed
• Affects Version/s: 2.8.1
• Fix Version/s: 2.9
• Release Note: Added JVM option to support CPU load metric on java 11 and higher
• Ignite Flags: Docs Required, Release Notes Required
• Assignee: Mirza Aliev
• Reporter: Mirza Aliev
• Created: 28/Jul/20 07:23
• Updated: 07/Aug/20 07:30
• Resolved: 31/Jul/20 11:07

Description

Start cluster under Java 11.

Observed:
CpuLoad metric will return -1

Expected:
Real CpuLoad.

We investigated this issue and found that under Java 11 code failed with following trace:

class org.apache.ignite.IgniteException: Failed to get property value [property=processCpuTime, obj=com.sun.management.internal.OperatingSystemImpl@1dd92fe2] at org.apache.ignite.internal.util.IgniteUtils.property(IgniteUtils.java:8306) at org.apache.ignite.internal.managers.discovery.GridDiscoveryManager$MetricsUpdater.getCpuLoad(GridDiscoveryManager.java:3131) at org.apache.ignite.internal.managers.discovery.GridDiscoveryManager$MetricsUpdater.run(GridDiscoveryManager.java:3093) at org.apache.ignite.internal.processors.timeout.GridTimeoutProcessor$CancelableTask.onTimeout(GridTimeoutProcessor.java:364) at org.apache.ignite.internal.processors.timeout.GridTimeoutProcessor$TimeoutWorker.body(GridTimeoutProcessor.java:233) at org.apache.ignite.internal.util.worker.GridWorker.run(GridWorker.java:119) at java.base/java.lang.Thread.run(Thread.java:834) Caused by: java.lang.reflect.InaccessibleObjectException: Unable to make public long com.sun.management.internal.OperatingSystemImpl.getProcessCpuTime() accessible: module jdk.management does not "opens com.sun.management.internal" to unnamed module @35fb3008 at java.base/java.lang.reflect.AccessibleObject.checkCanSetAccessible(AccessibleObject.java:340) at java.base/java.lang.reflect.AccessibleObject.checkCanSetAccessible(AccessibleObject.java:280) at java.base/java.lang.reflect.Method.checkCanSetAccessible(Method.java:198) at java.base/java.lang.reflect.Method.setAccessible(Method.java:192) at org.apache.ignite.internal.util.IgniteUtils.property(IgniteUtils.java:8297) ... 6 more

Under Java 8 metric has expected value.

 

Solution:

The behaviour is expected because in Java 11 the CPU load metrics is moved to JDK internal module which is not accessible by default. Adding the following line to the jvm in which Ignite node is started should solve the issue:

--add-opens jdk.management/com.sun.management.internal=ALL-UNNAMED

Issue Links

• links to: GitHub Pull Request #8088