Simulator

Joulie simulator provides a digital-twin path for controlled evaluation.

It keeps scheduling behavior real while simulating telemetry/control dynamics and workload progression.

The simulator mirrors the real Joulie architecture. The operator, agent, and scheduler extender are the real components running against simulated hardware:

• the real operator computes desired state (NodeTwin.spec, NodeTwin.status),
• the real agent (pool mode) realizes caps via HTTP against the simulator,
• the real scheduler extender reads NodeTwin.status and applies workload-class-aware scoring,
• workloads carry WorkloadProfile-compatible fields (criticality, migratability, cap sensitivity),
• facility stress model (simulator/pkg/facility) provides PSU and cooling stress signals.

The heterogeneous benchmark (experiments/02-heterogeneous-benchmark/) demonstrates the full architecture across three baselines: no Joulie, static partition, and queue-aware policy with scheduler extender steering.

Use simulator docs after you are familiar with the core operator/agent control loop in Getting Started + Architecture.

Read in this order

1. Workload and Power Simulator
2. Workload Generation
3. Workload Distributions
4. Kubernetes AI Workloads
5. Workload Simulator
6. Power Simulator
7. Hardware Modeling
8. Simulator Metrics

Simulator architecture diagram

See detailed explanation in:

• Workload and Power Simulator