Files
kernbench2/docs/diagrams
ywkang 0bf220fed0 Switch PE_DMA perf plots to Effective BW utilization
Replaces the latency-breakdown stacked bars with a single utilization
bar per scenario. Each bar shows ``effective_bw / peak_bottleneck_bw``
with both values annotated, and a horizontal "single-path peak" line at
100 %. The colour band (green ≥70 %, amber ≥40 %, red <40 %) makes the
no-congestion distance roll-off scannable at a glance.

Definitions:
  effective_bw = (total bytes transferred) / wall-clock time
    no_congestion: nbytes / total_ns
    congestion:    n_issuers × nbytes / makespan_ns  (aggregate)
  peak_bw      = min(edge.bw_gbs) on first issuer's path
  util_pct     = effective_bw / peak_bw × 100

The congestion graph shows that 8×PE eastbound exceeds 100 % of a
single-path peak (106.4 %): UCIe-N's 4 connections × 128 GB/s give
512 GB/s of aggregate eastbound capacity, so concurrent issuers across
disjoint conns sum past any single conn's 128 GB/s. The 8×PE→pe0_slice
hotspot reaches 91.7 %, almost saturating the shared r0c0→hbm_ctrl.pe0
bottleneck — the simulator's address-based PC striping + per-flit
arbitration model amortises the cost cleanly.

Self-verification updated to BW invariants:
  (1) effective BW shrinks as topological distance grows
  (2) util_pct ∈ (0, 250 %]
  (3) single-issuer util_pct ≤ 100 %
  (4) effective_bw = nbytes / total_ns for single requests
  (5) congestion aggregate BW grows monotonically with issuer count
      on the hot-target series
  (6) 8-PE all-hit-pe0 saturates ≥ 70 % of shared peak

All checks PASS at the current model.

The CSV retains all breakdown components (pe_setup, noc_mesh, ucie,
fabric, streaming, hbm_ctrl, contention) so a future replot can still
recover the latency-breakdown view without re-running the simulator.

Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>
2026-05-15 07:59:45 -07:00
..
2026-03-18 11:47:48 -07:00
2026-03-18 11:47:48 -07:00
2026-03-18 11:47:48 -07:00
2026-03-18 11:47:48 -07:00

Generated Diagrams

This directory contains diagrams generated from topology compilation.

What these files are

  • Derived artifacts generated from:
    • compiled topology graph
    • distance (accumulated latency) metadata
    • view/layout rules (ADR-0005)

These files are meant for quick visual inspection and review.

Default outputs

  • SIP view: sip_view.mmd (and/or sip_view.dot)
  • CUBE view: cube_view.mmd (and/or cube_view.dot)
  • PE view: pe_view.mmd (and/or pe_view.dot)

How to preview

  • In VS Code:
    • open .mmd or .md containing Mermaid blocks and use Markdown Preview
    • for .dot, use a Graphviz preview extension or dot -Tpng

Notes

  • Diagrams are representative and distance-aware by default.
  • Instance indices are not required unless debugging asymmetry.
  • Outputs should be deterministic for the same topology and rules.