diff --git a/jcl/src/jdk.management/share/classes/com/ibm/lang/management/internal/ExtendedOperatingSystemMXBeanImpl.java b/jcl/src/jdk.management/share/classes/com/ibm/lang/management/internal/ExtendedOperatingSystemMXBeanImpl.java
index 6cf1a32adfe..772e9b71500 100644
--- a/jcl/src/jdk.management/share/classes/com/ibm/lang/management/internal/ExtendedOperatingSystemMXBeanImpl.java
+++ b/jcl/src/jdk.management/share/classes/com/ibm/lang/management/internal/ExtendedOperatingSystemMXBeanImpl.java
@@ -245,6 +245,12 @@ public final String getHardwareModel() throws UnsupportedOperationException {
/* Returns the number of CPU's online at this very moment. */
private native int getOnlineProcessorsImpl();
+ /**
+ * Check if the CpuLoadCompatibility flag is set.
+ * @return if the CpuLoadCompatibility flag is set
+ */
+ private static native boolean hasCpuLoadCompatibilityFlag();
+
/**
* {@inheritDoc}
*/
@@ -263,8 +269,8 @@ public final synchronized double getProcessCpuLoad() {
}
latestCpuTime = cpuTime;
- /* First call to this method should -1, since we don't have any previous
- * CPU times (or timestamp) to compute CPU load against.
+ /* If no previous timestamps is set, the default behaviour is to return -1.
+ * If the compatibility flag is set, return 0 to match the behaviour of RI.
*/
if (-1 == oldTime) {
/* Save current counters; next invocation onwards, we use these to
@@ -272,7 +278,11 @@ public final synchronized double getProcessCpuLoad() {
*/
oldTime = interimTime = latestTime;
oldCpuTime = interimCpuTime = latestCpuTime;
- return CpuLoadCalculationConstants.ERROR_VALUE;
+ if (hasCpuLoadCompatibilityFlag()) {
+ return 0;
+ } else {
+ return CpuLoadCalculationConstants.ERROR_VALUE;
+ }
}
/* If a sufficiently long interval has elapsed since last sampling, calculate using
diff --git a/runtime/jcl/common/extendedosmbean.c b/runtime/jcl/common/extendedosmbean.c
index 66c88379428..590c3eeadd2 100644
--- a/runtime/jcl/common/extendedosmbean.c
+++ b/runtime/jcl/common/extendedosmbean.c
@@ -518,6 +518,20 @@ Java_com_ibm_lang_management_internal_ExtendedOperatingSystemMXBeanImpl_getHardw
return (NULL == str) ? NULL : (*env)->NewStringUTF(env, str);
}
+/**
+ * Check if the CpuLoadCompatibility flag is set.
+ *
+ * @param env instance of JNIEnv
+ * @param unusedClass
+ *
+ * @return if the CpuLoadCompatibility flag is set
+ */
+jboolean JNICALL
+Java_com_ibm_lang_management_internal_ExtendedOperatingSystemMXBeanImpl_hasCpuLoadCompatibilityFlag(JNIEnv *env, jclass unusedClass) {
+ J9JavaVM *vm = ((J9VMThread *)env)->javaVM;
+ return J9_ARE_ALL_BITS_SET(vm->extendedRuntimeFlags2, J9_EXTENDED_RUNTIME2_CPU_LOAD_COMPATIBILITY);
+}
+
/**
* Returns the maximum number of file descriptors that can be opened in a process.
*
diff --git a/runtime/jcl/common/mgmtosext.c b/runtime/jcl/common/mgmtosext.c
index 15cb77a373a..b516311ce88 100644
--- a/runtime/jcl/common/mgmtosext.c
+++ b/runtime/jcl/common/mgmtosext.c
@@ -83,6 +83,8 @@ jdouble JNICALL
Java_com_ibm_lang_management_internal_ExtendedOperatingSystemMXBeanImpl_getSystemCpuLoadImpl(JNIEnv *env, jobject instance) {
PORT_ACCESS_FROM_ENV(env);
OMRPORT_ACCESS_FROM_J9PORT(PORTLIB);
+
+ J9JavaVM *vm = ((J9VMThread *)env)->javaVM;
double cpuLoad = 0.0;
intptr_t portLibraryStatus = omrsysinfo_get_CPU_load(&cpuLoad);
@@ -95,6 +97,12 @@ Java_com_ibm_lang_management_internal_ExtendedOperatingSystemMXBeanImpl_getSyste
case OMRPORT_ERROR_SYSINFO_NOT_SUPPORTED:
portLibraryStatus = -3;
break;
+ case OMRPORT_ERROR_INSUFFICIENT_DATA:
+ portLibraryStatus =
+ J9_ARE_ALL_BITS_SET(vm->extendedRuntimeFlags2, J9_EXTENDED_RUNTIME2_CPU_LOAD_COMPATIBILITY)
+ ? 0
+ : -1;
+ break;
default:
portLibraryStatus = OMRPORT_ERROR_OPFAILED;
break;
diff --git a/runtime/jcl/exports.cmake b/runtime/jcl/exports.cmake
index fd880fb10bb..c0497124d40 100644
--- a/runtime/jcl/exports.cmake
+++ b/runtime/jcl/exports.cmake
@@ -228,6 +228,7 @@ omr_add_exports(jclse
Java_com_ibm_lang_management_internal_ExtendedOperatingSystemMXBeanImpl_getSystemCpuLoadImpl
Java_com_ibm_lang_management_internal_ExtendedOperatingSystemMXBeanImpl_getTotalPhysicalMemoryImpl
Java_com_ibm_lang_management_internal_ExtendedOperatingSystemMXBeanImpl_getTotalProcessorUsageImpl
+ Java_com_ibm_lang_management_internal_ExtendedOperatingSystemMXBeanImpl_hasCpuLoadCompatibilityFlag
Java_com_ibm_lang_management_internal_ExtendedOperatingSystemMXBeanImpl_isDLPAREnabled
Java_com_ibm_lang_management_internal_ExtendedRuntimeMXBeanImpl_getVMIdleStateImpl
Java_com_ibm_lang_management_internal_JvmCpuMonitor_getThreadCategoryImpl
diff --git a/runtime/jcl/uma/se7_exports.xml b/runtime/jcl/uma/se7_exports.xml
index 25289847126..d62abf443f7 100644
--- a/runtime/jcl/uma/se7_exports.xml
+++ b/runtime/jcl/uma/se7_exports.xml
@@ -67,6 +67,7 @@
+
diff --git a/runtime/oti/j9consts.h b/runtime/oti/j9consts.h
index 98ace0c65cd..479a8d3cfa5 100644
--- a/runtime/oti/j9consts.h
+++ b/runtime/oti/j9consts.h
@@ -362,7 +362,7 @@ extern "C" {
#define J9_EXTENDED_RUNTIME2_USE_CONTAINER_SUPPORT 0x200000
#define J9_EXTENDED_RUNTIME2_SHOW_CARRIER_FRAMES 0x400000
#define J9_EXTENDED_RUNTIME2_CRIU_SINGLE_THROW_BLOCKING_EXCEPTIONS 0x800000
-#define J9_EXTENDED_RUNTIME2_UNUSED_0x1000000 0x1000000
+#define J9_EXTENDED_RUNTIME2_CPU_LOAD_COMPATIBILITY 0x1000000
#define J9_OBJECT_HEADER_AGE_DEFAULT 0xA /* OBJECT_HEADER_AGE_DEFAULT */
#define J9_OBJECT_HEADER_SHAPE_MASK 0xE /* OBJECT_HEADER_SHAPE_MASK */
diff --git a/runtime/oti/jclprots.h b/runtime/oti/jclprots.h
index 669aa7e83d7..503eb11747a 100644
--- a/runtime/oti/jclprots.h
+++ b/runtime/oti/jclprots.h
@@ -1166,6 +1166,8 @@ Java_com_ibm_lang_management_internal_ExtendedOperatingSystemMXBeanImpl_getOnlin
jstring JNICALL
Java_com_ibm_lang_management_internal_ExtendedOperatingSystemMXBeanImpl_getHardwareModelImpl(JNIEnv *env, jobject obj);
+jboolean JNICALL
+Java_com_ibm_lang_management_internal_ExtendedOperatingSystemMXBeanImpl_hasCpuLoadCompatibilityFlag(JNIEnv *env, jclass unusedClass);
/**
* Returns the maximum number of file descriptors that can be opened in a process.
*
diff --git a/runtime/oti/jvminit.h b/runtime/oti/jvminit.h
index 6eddffbf5b3..221f3171582 100644
--- a/runtime/oti/jvminit.h
+++ b/runtime/oti/jvminit.h
@@ -415,6 +415,8 @@ enum INIT_STAGE {
#define VMOPT_XXDISABLEENSUREHASHED "-XX:-EnsureHashed:"
#define VMOPT_XXOPENJ9COMMANDLINEENV "-XX:+OpenJ9CommandLineEnv"
#define VMOPT_XXNOOPENJ9COMMANDLINEENV "-XX:-OpenJ9CommandLineEnv"
+#define VMOPT_XXCPULOADCOMPATIBILITY "-XX:+CpuLoadCompatibility"
+#define VMOPT_XXNOCPULOADCOMPATIBILITY "-XX:-CpuLoadCompatibility"
#if defined(J9VM_ZOS_3164_INTEROPERABILITY)
#define VMOPT_XXENABLE3164INTEROPERABILITY "-XX:+Enable3164Interoperability"
diff --git a/runtime/vm/jvminit.c b/runtime/vm/jvminit.c
index fbb473c8b12..f6388c994aa 100644
--- a/runtime/vm/jvminit.c
+++ b/runtime/vm/jvminit.c
@@ -4113,6 +4113,14 @@ processVMArgsFromFirstToLast(J9JavaVM * vm)
}
#endif /* JAVA_SPEC_VERSION >= 19 */
+ {
+ IDATA cpuLoadCompatibility = FIND_AND_CONSUME_VMARG(EXACT_MATCH, VMOPT_XXCPULOADCOMPATIBILITY, NULL);
+ IDATA noCpuLoadCompatibility = FIND_AND_CONSUME_VMARG(EXACT_MATCH, VMOPT_XXNOCPULOADCOMPATIBILITY, NULL);
+ if (cpuLoadCompatibility > noCpuLoadCompatibility) {
+ vm->extendedRuntimeFlags2 |= J9_EXTENDED_RUNTIME2_CPU_LOAD_COMPATIBILITY;
+ }
+ }
+
return JNI_OK;
}