Task · SKT-0072

Replace frozen Datadog receiver system values with grounded deterministic mechanics

Description

The shipped Kubernetes receiver emits lifetime-flat idle CPU, zero context switches and unused memory despite modelling a running Agent and collector. Artifact envelopes are correct; captured values are elided and cannot establish plausibility.

Acceptance Criteria

Definition of Done

Implementation Plan

L1 owns receiver mechanics and focused proof; root reviews grounding, applies documentation proposals, compares inventory and runs final gates.

Implementation Notes

Root independently verified current Agent CPU formulas: system includes IRQ+softIRQ and interrupt repeats them; guest is also outside the denominator. The seven named percentages sum to 100 plus interrupt plus guest, not 100. Goal acceptance corrected under delegated authority to source-faithful overlap and disjoint elapsed-time accounting. Grounded zero modes and fixed declared hardware capacity must not be made artificially variable. High materiality; envelopes and frozen seams unchanged.

Landed receiver mechanics and documentation in 33f4cf42bd8ec615a2846fe6e31d888078b69459. Same-producer baseline grounding and corrected CPU overlap arithmetic are retained in codex/scratch/wave-2026-09-18/l1/source-and-baseline.md. Failing-before, passing-after, receiver separation, band and envelope controls passed. CodeRabbit complete with one minor core-set test gap, fixed and package retested (0.507s); no findings left. Root just dump confirmed the entire OTLP metric section unchanged; unrelated time-sampled inventory differences retained separately. Root integrated just check passed, including fidelity with only the existing exemption and producer bound 203. just gen is not applicable: no blueprint field, config struct or skill changed.

Final Summary

Completed at source commit 33f4cf42bd8ec615a2846fe6e31d888078b69459. Replaces lifetime-flat busy CPU, context switches, load and memory with deterministic bounded observations; preserves fixed hardware capacity, observed-zero modes and all native envelopes. Host mode remains one family. Evidence: codex/scratch/wave-2026-09-18/l1/, coderabbit-receiver.ndjson, inventory-comparison.txt and check-precommit.log. Final exact-SHA CI is recorded in the campaign report after tracker reconciliation.

View the source file on GitHub