pinpoint-apm/pinpoint · warning

Unknown CpuLoadMetric : {}

Error message

Unknown CpuLoadMetric : {}

What it means

CpuLoadMetricProvider.createCpuLoadMetric logs 'Unknown CpuLoadMetric' when Class.forName succeeds but the loaded class has no public no-arg constructor (NoSuchMethodException). It returns CpuLoadMetric.UNSUPPORTED_CPU_LOAD_METRIC so the agent continues without CPU load metrics. This branch is distinct from the general ReflectiveOperationException branch that logs 'Error creating CpuLoadMetric'.

Source

Thrown at agent-module/profiler/src/main/java/com/navercorp/pinpoint/profiler/context/provider/stat/cpu/CpuLoadMetricProvider.java:85

        if (jvmType == JvmType.IBM) {
            return IBM_CPU_LOAD_METRIC;
        }
        return null;
    }

    private CpuLoadMetric createCpuLoadMetric(String classToLoad) {
        if (classToLoad == null) {
            return CpuLoadMetric.UNSUPPORTED_CPU_LOAD_METRIC;
        }
        try {
            @SuppressWarnings("unchecked")
            Class<CpuLoadMetric> cpuLoadMetricClass = (Class<CpuLoadMetric>) Class.forName(classToLoad);
            try {
                Constructor<CpuLoadMetric> cpuLoadMetricConstructor = cpuLoadMetricClass.getConstructor();
                return cpuLoadMetricConstructor.newInstance();
            } catch (NoSuchMethodException e) {
                logger.warn("Unknown CpuLoadMetric : {}", classToLoad);
                return CpuLoadMetric.UNSUPPORTED_CPU_LOAD_METRIC;
            }
        } catch (ReflectiveOperationException e) {
            logger.warn("Error creating CpuLoadMetric [" + classToLoad + "]");
            return CpuLoadMetric.UNSUPPORTED_CPU_LOAD_METRIC;
        }
    }
}

View on GitHub (pinned to 744c3d3075)

Solutions

1. Verify the class named in the log has a public no-arg constructor; add one if it is your custom implementation
2. Check whether your Pinpoint version's class map matches the target OS/JVM and upgrade the agent if the platform is newer than the mapping
3. Confirm the fallback UNSUPPORTED_CPU_LOAD_METRIC is acceptable — if CPU metrics matter, provide a compatible implementation

Example fix

// before
class MyCpuLoadMetric implements CpuLoadMetric {
    MyCpuLoadMetric(OperatingSystemMXBean os) { ... }
}
// after
class MyCpuLoadMetric implements CpuLoadMetric {
    public MyCpuLoadMetric() { this(getPlatformBean()); }
    MyCpuLoadMetric(OperatingSystemMXBean os) { ... }
}

try { Class<?> c = Class.forName(metricClassName); c.getConstructor(); } catch (ClassNotFoundException | NoSuchMethodException e) { /* resolve before enabling cpu metrics */ }

try { return ctor.newInstance(); } catch (NoSuchMethodException e) { logger.warn("Unknown CpuLoadMetric : {}", classToLoad); return CpuLoadMetric.UNSUPPORTED_CPU_LOAD_METRIC; }

When it happens

Trigger: A CPU load metric class name (built from OS/JVM type/version mapping) resolves to a class that changed its constructor signature or was replaced with one requiring arguments.

Common situations: JVM/OS mapping table points at a class refactored between Pinpoint versions; custom CpuLoadMetric implementation without a no-arg constructor configured for the platform.

Related errors

• Error creating CpuLoadMetric [{}]
• Unknown FileDescriptorMetric : {}
• constructor not found
• ModuleSupportFactory() initialize fail
• BufferMetric initialize fail: {}

AI-assisted analysis of pinpoint-apm/pinpoint@744c3d3075 (2026-09-07). Data as JSON: /api/errors/4d9327ae68364611. Report an issue: GitHub.