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Workload Mapping Basics: Operators to Hardware: Reports and Metrics

Reports and Metrics for Workload Mapping Basics: Operators to Hardware.

Reports and metrics

Reports and Metrics for Workload Mapping Basics: Operators to Hardware is anchored on Percent of model FLOPs sustained on hardware and memory-stall fraction by layer type.. Convert measurements into mechanism-backed decisions with clear owner accountability.

A useful report explains why movement happened, not only that movement happened.

Evidence matrix

diagram
EVIDENCE MATRIX - Workload Mapping Basics: Operators to Hardware

+-----------------------------+--------------------------------+--------------------------------+---------------------------+
| Evidence                    | Tells you                      | Does not prove                 | Next action               |
+-----------------------------+--------------------------------+--------------------------------+---------------------------+
| occupancy + timeline traces | where utilization is lost      | precise root cause             | map to memory and schedule|
| cache/SRAM/bandwidth stats  | data movement pressure         | model-level quality impact     | correlate with quality run|
| counter + profile alignment | bottleneck class confidence    | rollout safety                 | run full regression matrix|
| thermal/power telemetry     | sustained operating envelope   | correctness closure            | pair with verification    |
| before/after scenario pack  | mitigation movement            | long-tail stability            | execute guardrail replay  |
+-----------------------------+--------------------------------+--------------------------------+---------------------------+
  • Track Percent of model FLOPs sustained on hardware and memory-stall fraction by layer type. on representative production workloads.

  • Include build/runtime metadata in every report header.

  • Correlate throughput, latency, and quality before rollout decisions.

  • Call out contradictory evidence explicitly.

AI accelerator deep dive

Accelerator selection quality depends on workload realism and full-stack delivery readiness.

Concept diagram

diagram
ACCELERATOR LANDSCAPE

model shape + SLA + power budget
  -> candidate platform shortlist
  -> benchmark under production-like load
  -> choose architecture + stack strategy

Metric graph

diagram
PLATFORM TRADE CURVE

throughput      ███████████
latency         ███████
energy          ████████
engineering risk █████

Metrics and artifacts to collect

  • workload fit matrix

  • latency-throughput sweep

  • perf-per-watt dashboard

  • owner and risk map

Mini case study

A platform looked best on synthetic GEMM but lost in production due to runtime overhead and memory-tail behavior.

Debug branches

  • Validate workload representativeness

  • Check software-stack maturity

  • Tie KPI gains to product SLA

Senior review question

Ask: which first-principles bottleneck class explains the symptom, and what artifact proves it reproducibly?

Key takeaways

  • Tie every accelerator claim to a reproducible workload slice and one primary metric trend.

  • Prefer bounded fixes with clear owner and rollback boundary over broad tuning bundles.

Common pitfalls

  • Optimizing synthetic kernels without production-shape validation.

  • Reading average latency while ignoring p95 and p99 behavior.

  • Declaring sparse or precision wins without fallback and quality evidence.

Report interpretation

Workload mapping converts a graph of operators into executable kernels that respect compute shape, memory hierarchy, and interconnect limits. Convolutions and GEMMs tend to map well to matrix engines when tiling aligns with local SRAM capacity, while attention, reductions, and control-heavy layers can expose synchronization or bandwidth bottlenecks. Effective mapping balances tile size, fusion boundaries, quantization format, and data-layout transforms so arithmetic units stay busy without overflowing memory traffic budgets. Compile-time scheduling plus runtime autotuning is usually required because the best plan varies with sequence length, batch size, and model variant. A useful explanation always ties observed symptom to a repeatable path where useful work was blocked, delayed, or diluted by overhead.

Use Percent of model FLOPs sustained on hardware and memory-stall fraction by layer type. as an alarm, then anchor action using hard evidence such as Operator-to-kernel mapping sheet with tiling assumptions, fusion plan, and expected bottleneck class..

Platform choice quality depends on workload realism, software maturity, and total-system economics. Senior reviews expect a chain of proof: workload intent -> mapping -> hardware behavior -> product impact.

For Workload Mapping Basics: Operators to Hardware, reports should explain why Percent of model FLOPs sustained on hardware and memory-stall fraction by layer type. moved and which path consumed budget first.