Patterns
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Resource-Aware Scheduling(RAS)

Dynamically schedules AI tasks based on available computational resources and constraints

Complexity: highPattern

Core Mechanism

Resource-Aware Scheduling dynamically matches AI tasks with compute resources (CPU/GPU/TPU, memory, bandwidth) using live telemetry and SLO/cost constraints. It combines techniques like dynamic batching, queueing, priority and preemption, model placement, and autoscaling to meet latency/throughput targets while maximizing utilization and respecting power/thermal and budget limits.

Workflow / Steps

  1. Profile tasks and models: latency SLOs, batchability, memory footprints (KV cache/weights), throughput targets.
  2. Instrument resources: collect CPU/GPU utilization, memory, queue depth, temperature, power, and cost signals.
  3. Admission control & routing: classify request priority/tier; route to suitable model/instance/region.
  4. Scheduling & batching: form dynamic batches within SLO; apply priority, preemption, or isolation where needed.
  5. Autoscaling & placement: scale replicas by queue/latency; place models to satisfy memory/affinity constraints.
  6. Feedback control: monitor SLO attainment; adapt batch size/concurrency, and adjust priorities/budgets.

Best Practices

Use dynamic batching with per-tier latency budgets; separate low-latency from best-effort queues.
Right-size model placement by memory (weights + KV cache) and compute; avoid page thrash and OOM.
Implement priority and preemption for urgent requests; protect background jobs with quotas.
Tune concurrency per instance based on utilization and headroom; avoid head-of-line blocking.
Autoscale on queue depth and p95 latency; use warm pools for burstiness; prefer bin-packing for cost.
Instrument end-to-end: request, queue, batch, inference, and postprocessing stages with traces/metrics.
Apply regional/zone routing and model replicas for resilience; drain gracefully during rollouts.
Cap token/context budgets; compress/stream to meet SLOs and control spend.

When NOT to Use

  • Ultra-simplified/homogeneous workloads where static round-robin meets SLOs cheaply.
  • Hard real-time control loops where any batching/queuing overhead risks deadline misses.
  • Single-tenant, overprovisioned environments with negligible contention and stable load.

Common Pitfalls

  • Over-batching causing p95/p99 latency regressions; ignoring per-tier SLO budgets.
  • Insufficient GPU memory accounting for KV cache/token growth โ†’ OOMs and restarts.
  • Hotspot queues and head-of-line blocking; lack of isolation between tiers/tenants.
  • Reactive-only autoscaling with cold start penalties; no warm capacity for bursts.
  • Poor observability: missing queue time vs. inference time breakdown; blind tuning.

Key Features

Real-time resource telemetry and SLO-aware routing
Dynamic batching and token-aware scheduling
Priority queues, preemption, and isolation per tier/tenant
Placement aware of memory/affinity and NUMA/GPU topology
Autoscaling with warm pools and bin-packing for cost
End-to-end traces, metrics, and policy-driven budgets

KPIs / Success Metrics

  • Latency: p50/p95 end-to-end and queue time share; SLO attainment rate per tier.
  • Throughput: requests/s and tokens/s per instance and fleet; batch effectiveness.
  • Utilization: GPU SM/memory utilization, CPU utilization, saturation indicators.
  • Cost and efficiency: cost/request, tokens per dollar, energy per token.
  • Stability: error rate, OOM/restart rate, autoscale convergence time.

Token / Resource Usage

  • Budget input/output tokens per tier; enforce max context and apply compression/summarization.
  • Track KV cache growth vs. batch size and sequence length; reserve headroom to prevent OOM.
  • Use continuous/dynamic batching to improve tokens/s while honoring per-request deadlines.
  • Prefer streaming for tight SLOs; cut off long generations or down-tier models on budget pressure.

Best Use Cases

  • Multi-tenant LLM APIs with tiered latency/cost SLOs and bursty demand.
  • Real-time assistants and chat where TTFT and p95 latency are critical.
  • Batch/stream inference services in cloud and Kubernetes with autoscaling.
  • Edge/mobile deployments balancing battery, thermal limits, and offline modes.
  • Autonomous systems requiring deadline-aware perception/planning pipelines.

References & Further Reading

Patterns

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