apache/skywalking · error · IllegalArgumentException

Uncreated metrics {}

Error message

Uncreated metrics {}

What it means

buildMetrics(name, dataType) hands a caller a fresh AcceptableValue instance from the prototype registered under that metric name. If meterPrototypes has no entry for the name — the metric was never created via MeterSystem.create, was removed, or the name is spelled differently — it throws 'Uncreated metrics <name>'.

Source

Thrown at oap-server/server-core/src/main/java/org/apache/skywalking/oap/server/core/analysis/meter/MeterSystem.java:727

            throw new UnexpectedException(e.getMessage(), e);
        }
    }

    /**
     * Create an {@link AcceptableValue} instance for streaming calculation. AcceptableValue instance is stateful,
     * shouldn't do {@link AcceptableValue#accept(MeterEntity, Object)} once it is pushed into {@link
     * #doStreamingCalculation(AcceptableValue)}.
     *
     * @param metricsName A defined metrics name. Use {@link #create(String, String, ScopeType, Class)} to define a new
     *                    one.
     * @param dataType    class type of the input of {@link AcceptableValue}
     * @return usable an {@link AcceptableValue} instance.
     */
    public <T> AcceptableValue<T> buildMetrics(String metricsName,
                                               Class<T> dataType) {
        MeterDefinition meterDefinition = meterPrototypes.get(metricsName);
        if (meterDefinition == null) {
            throw new IllegalArgumentException("Uncreated metrics " + metricsName);
        }
        if (!meterDefinition.getDataType().equals(dataType)) {
            throw new IllegalArgumentException(
                "Unmatched metrics data type, request for " + dataType.getName()
                    + ", but defined as " + meterDefinition.getDataType());
        }

        return meterDefinition.getMeterPrototype().createNew();
    }

    /**
     * Active the {@link MetricsStreamProcessor#in(Metrics)} for streaming calculation.
     *
     * @param acceptableValue should only be created through {@link #create(String, String, ScopeType, Class)}
     */
    public void doStreamingCalculation(AcceptableValue acceptableValue) {
        final long timeBucket = acceptableValue.getTimeBucket();
        if (timeBucket == 0L) {

View on GitHub (pinned to 102af09b4a)

Solutions

1. Ensure create(metricsName, functionName, scopeType, dataType) ran successfully for exactly that name before any buildMetrics call — check OAP startup logs for rule apply errors
2. Align the name strings (case-sensitive) between the create site and the buildMetrics site
3. If the metric was hot-removed, stop the emitting pipeline or re-apply the rule that defines it

Example fix

// before
AcceptableValue<Long> v = meterSystem.buildMetrics("service_cpm", Long.class);
// rule defines "service_cpm_sum" -> Uncreated metrics service_cpm

// after
AcceptableValue<Long> v = meterSystem.buildMetrics("service_cpm_sum", Long.class);

// MeterSystem has no public lookup; track the names you created
Set<String> created = ConcurrentHashMap.newKeySet();
created.add(name); // after successful meterSystem.create(name, ...)
if (!created.contains(name)) throw new IllegalStateException("Metric not created: " + name);
AcceptableValue<Long> v = meterSystem.buildMetrics(name, Long.class);

try {
    AcceptableValue<Long> v = meterSystem.buildMetrics(name, Long.class);
} catch (IllegalArgumentException e) {
    if (e.getMessage().startsWith("Uncreated metrics")) {
        log.warn("Metric {} not registered yet (rule not applied or removed); dropping sample", name);
        return; // drop or buffer instead of crashing the receiver
    }
    throw e;
}

When it happens

Trigger: MAL/LAL or custom analyzer code calls buildMetrics for a metric whose create() never ran on this node (e.g. the rule defining it failed earlier or was hot-removed); a typo or case difference between the create() name and the buildMetrics name; calling buildMetrics during startup before the meter rules were applied.

Common situations: Custom receiver plugins that reference a metric defined in a MAL file that failed to load; race at OAP boot between data arrival and rule application; renaming a metric in config but not in the code that reads it; a removed rule while buffered data still references the metric.

Related errors

• {} has been defined, but calculate function or/are scope typ
• Unmatched metrics data type, request for {}, but defined as
• MeterSystem unavailable for MAL compile of {sourceName}
• Function {} doesn't inherit from Metrics.
• buckets and values can't be null.

AI-assisted analysis of apache/skywalking@102af09b4a (2026-08-14). Data as JSON: /api/errors/e29ca19544eb68cf. Report an issue: GitHub.