init

[mhlidd]

What Does This Do

Follow-up to the parent PR for maximo/otlp-runtime-metrics that expands the OTLP JVM runtime metrics surface and gates Development-status metrics behind a new opt-out flag.

New config

• dd.metrics.otel.experimental.enabled (default: true) — mirrors OTel's otel.instrumentation.runtime-telemetry.emit-experimental-metrics. When false, only metrics marked Stable in the OTel JVM semantic conventions are emitted; Development-status metrics are suppressed.

Metrics added or reclassified (all under the datadog.jvm.runtime scope, OTel-native names)

Metric	OTel status	When emitted
jvm.memory.used_after_last_gc	Stable	Always (moved into the always-on memory group)
jvm.memory.init	Development	Only when experimental flag is on
jvm.buffer.memory.used / limit / count	Development	Only when experimental flag is on
jvm.system.cpu.utilization	Development	Only when experimental flag is on
jvm.system.cpu.load_1m	Development	Only when experimental flag is on
jvm.file_descriptor.count / limit	Development	Only when experimental flag is on, and only on Unix-like JVMs (UnixOperatingSystemMXBean)

Value-guard alignment with OTel reference implementation

• jvm.memory.limit and jvm.memory.init now skip recording only when getMax() / getInit() returns the documented -1 sentinel (was > 0, which incorrectly also skipped legitimate 0 values).
• All other per-metric guards (>= 0, null checks) match the corresponding callbacks in io.opentelemetry.instrumentation.runtimetelemetry.internal.*.

Misc

• Extracted sunOsBean() helper to remove duplicated instanceof OperatingSystemMXBean cast logic between registerCpuMetrics() and the new registerSystemCpuMetrics().
• Added debug logs when an MXBean isn't available so it's obvious why a metric didn't show up.
• Test coverage extended to assert all newly added metric names are registered, with platform-conditional checks for the Unix-only file descriptor metrics.

Motivation

The parent PR established the OTLP JVM runtime metrics pipeline but only emitted a subset of the OTel JVM semantic conventions. This follow-up brings the surface in line with what opentelemetry-java-instrumentation's runtime-telemetry library emits, and adds the standard experimental-metrics opt-out so users who want only the Stable subset (smaller cardinality, fewer dashboard surprises) can disable Development metrics without losing the integration entirely.

Aligning the value guards with OTel's reference implementation prevents two real-world divergences:

1. Without the 0 vs -1 fix, uncapped non-heap pools (where getMax() == 0 on some JVM/version combos) would silently produce no jvm.memory.limit data point — they should publish 0 to indicate "no limit observed."
2. The experimental gate ensures dashboards built against OTel's stable-only output won't differ between OTel SDK collection and DD-agent collection.

Additional Notes

• No change to JMXFetch behavior beyond passing the new flag through JvmOtlpRuntimeMetrics.start(...). The OTLP_JMX_CONFIG-skip path is unchanged.
• The OTel-spec env var otel.instrumentation.runtime-telemetry.emit-experimental-metrics is captured in OtelEnvironmentConfigSource so an unmodified OTel-style config picks up the flag automatically.

Contributor Checklist

• Format the title according to the contribution guidelines
• Assign the type: and (comp: or inst:) labels in addition to any other useful labels
• Avoid using close, fix, or any linking keywords when referencing an issue
  Use solves instead, and assign the PR milestone to the issue
• Update the CODEOWNERS file on source file addition, migration, or deletion
• Update public documentation with any new configuration flags or behaviors

Jira ticket: [PROJ-IDENT]

[mhlidd]

@codex review

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[chatgpt-codex-connector]

Honor the documented OTel experimental flag

For users configuring OTLP metrics with the documented OpenTelemetry runtime option (OTEL_INSTRUMENTATION_RUNTIME_TELEMETRY_EMIT_EXPERIMENTAL_TELEMETRY, see https://docs.datadoghq.com/opentelemetry/integrations/runtime_metrics/), this lookup never sees the value because it checks otel.instrumentation.runtime-telemetry.emit-experimental-metrics instead. Since Config falls back to DEFAULT_METRICS_OTEL_EXPERIMENTAL_ENABLED = true, setting the documented OTel flag to false still emits the experimental JVM metrics gated by this change; map the telemetry property (or support both aliases) so the opt-out works.

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[mhlidd]

docs need to be updated.

[datadog-prod-us1-5]

✨ Fix all issues with BitsAI

⚠️ Warnings

🚦 98 Pipeline jobs failed

DataDog/apm-reliability/dd-trace-java | agent_integration_tests     

🔧 Fix in code (Fix with Cursor).

236 tests failed due to IllegalArgumentException thrown in ConfigHelper.java:162

DataDog/apm-reliability/dd-trace-java | test_base: [11, 2/4]     

🔧 Fix in code (Fix with Cursor).

632 tests failed due to IllegalArgumentException at ConfigHelper.java:162

DataDog/apm-reliability/dd-trace-java | test_base: [17, 3/4]     

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IllegalArgumentException thrown in multiple tests due to invalid parameters causing significant failures.

View all 98 failed jobs.

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