AI Accelerator Design · All levels

Input-Stationary Dataflow: Review Checklist

Review Checklist for Input-Stationary Dataflow.

Review checklist

Review Checklist for Input-Stationary Dataflow is anchored on Activation reuse factor and input-buffer read traffic per tera-operations for representative convolution and GEMM layers.. Convert measurements into mechanism-backed decisions with clear owner accountability.

  • Workload scope and SLA targets are explicit.

  • Environment metadata is locked and reproducible.

  • Mechanism classification is evidence-backed.

  • Owner, rollback trigger, and validation matrix are documented.

  • Owners signed: accelerator architect, memory hierarchy owner, compiler mapping owner, runtime scheduling owner.

AI accelerator deep dive

Dataflow choices are durable architecture decisions that shape memory and scheduling cost.

Concept diagram

diagram
DATAFLOW DECISION

input/output/weight stationary
  -> locality pattern
  -> movement cost
  -> throughput and power

Metric graph

diagram
DATAFLOW COST MIX

activation traffic   ███████
weight traffic       █████
partial-sum traffic  ██████

Metrics and artifacts to collect

  • reuse factor map

  • buffer pressure profile

  • NoC traffic mix

  • shape sensitivity analysis

Mini case study

A dataflow that won for convolution lost on attention-heavy batches due to activation movement pressure.

Debug branches

  • Segment by model family

  • Compare reuse vs movement

  • Re-check mapping assumptions under batch variance

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.

Review checklist explanation

Checklist quality determines whether teams close on proof or on optimism.

Minimum packet: metric trend (Activation reuse factor and input-buffer read traffic per tera-operations for representative convolution and GEMM layers.), artifact set (Traffic decomposition sheet showing activation residency, refill cadence, and bottleneck attribution by layer.), bottleneck class, owner fix, rollback trigger, and validation matrix.

If precision changes are involved, include quality guardrail evidence for each deployment slice.