Two strands bundled as the 1H-codesign-paper refresh unit:
(A) This session — single-op cost-model reflection (depends on 2d8271c):
- §2 Table 2 (tab:hw): split "FIXED per command" into "FIXED per
single-op command" (8 cycles) and "FIXED per composite command"
(40 cycles); §2 dispatch-overhead prose updated to the two-class split.
- §3.4 (sec:gemm-vs-async): rename paragraph headers + prose to
async-full / async-tiled; "atomic" -> "single-op" throughout; reframe
mechanism #3 from the old DMA-only fast-path to the single-op
fast-path. Headline narrative now: even with EVERY single-op cmd
(96 DMA + 48 dot + 47 add) charged the light 8-cycle FIXED, composite
still wins ~2.8x at K=3072 purely on command-count structure (1 vs
192 commands) -- down from the pre-D8 ~6.3x, and explicitly NOT a
modelling artifact. Numbers refreshed from the regenerated sweep:
async-full 3.83->3.91, async-tiled 1.14->~2.53, under-tile corner
1.06->1.21, depth-2 vs depth-inf spread <1%. New figure wired in.
- build/main.pdf rebuilt (tectonic); pdftotext-verified (no broken
refs; Table 2 split, single-op terms, 2.8x/2.53/192-host-commands
all present).
(B) Prior-session paper work riding along uncommitted: §4 all-reduce
deep-edit, §5 GQA, §6 discussion trims; milestone_1h_ccl.py plot
label "FSIM" -> "H2 2025 SW queue baseline"; regenerated diagrams
under docs/diagrams/** and gemm output PNGs under
1H_milestone_output/gemm/. (Composite-window gemm plots are
unaffected by D8 — D8 only changes single-op dispatch FIXED, which
the composite window excludes.)
All TODO items for the D8 single-op extension are now complete and
pushed across 3 commits (2d8271c cost-model+ADR+tests, 821bbf2 bench
harness, this paper refresh). Full regression green (826 passed, 1
skipped). No remaining work.
NOTE for review (carried from 2d8271c): ADR-0065's "2x CPU-offload win"
headline for GQA decode opt2 may want a refresh to the post-D8 ~1.87x.
Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>
§2 platform:
- Accuracy promoted from \paragraph to \subsection (sec:accuracy);
it sits at the same heading level as Why / Device / Latency / HW
config and so reads as a first-class component of the platform
description rather than a tail-end footnote.
- Three architecture diagrams (SIP, CUBE, PE) collapsed into one
figure* using subcaption: Fig.~\ref{fig:hw-arch}(a) SIP and (b)
CUBE side-by-side on row 1, (c) PE wide on row 2, total height
capped at ~40% of the page. Subfigure cross-references rewritten
to Fig.~ref{fig:hw-arch}\subref{...} in the body text. main.tex
now pulls in the subcaption package.
- Table 1 (modeled hardware configuration) promoted to table*
(two-column / full page width) and the row layout rewritten as a
4-column tabular so Hierarchy + PE + Command-issue sit on the
left and Memory + Interconnect sit on the right. The previous
single-column rendering was getting cut at the right edge of the
printed column.
§6 GQA:
- Removed the historical four-panel headline table (tab:gqa), the
two figures (fig:gqa-lat, fig:gqa-break), and the prose paragraph
that cited their per-panel numbers. Reason: the underlying
milestone-gqa-headline bench has been simplified in collaborator
commit 65c365f ("drop misleading single_user_/multi_user_
panels") and no longer reproduces that data, so the section was
left referencing a dataset the current bench cannot regenerate.
- The previously-added 4-cases long-context decode comparison is
now §6's only Results subsection, retitled to
"Results: long-context decode and parallelism strategies".
The headline GQA result that survives into the paper is therefore
the parallelism trade-off study (Case 4 / Cube-SP × PE-SP at 34 us
buying an 8x KV-memory reduction over the latency leaders).
Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>
The collaborator commit 7c346de added the comparative figures
(gqa_decode_long_ctx_4cases_{latency,memory,traffic}.png) but the
fused-GQA section still only referenced the four headline panels.
This commit closes that loop:
- New §6 subsection "Long-context decode: parallelism strategies"
added between Results and Analysis. It lays out the four
parallelism strategies (Cube-SP/Repl x PE-TP/SP) and pulls in the
three new figures.
- The discussion highlights the central trade: the fastest strategy
(Case 3, Cube-Repl x PE-SP at 20.2 us) requires replicating the
full KV cache to every CUBE, while Case 4 (Cube-SP x PE-SP, the
chosen design marked *) gives back ~14 us in exchange for an 8x
KV-memory reduction. Case 4's ~190 IPCQ copies + ~190 DMA reads
are precisely the on-device collective traffic PE_IPCQ and the
torus links of §5 are provisioned to absorb -- a direct payoff
of the communication-side codesign work.
- Connects back to §5 (PE_IPCQ / all-reduce) so the reader sees the
capstone arc: the GEMM enabler exposes the data-movement bound,
the communication enabler attacks it, and the long-context
parallelism study shows how the choice between the two extremes is
framed by KV memory vs. on-device collective traffic.
Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>
New `/paper` slash-command skill that synthesizes ADR/SPEC content and live
KernBench benchmark results into a sectioned LaTeX technical paper compiled
to PDF with Tectonic (auto-installed). The skill negotiates a TOC, grounds
every number in committed artifacts or fresh bench runs, and keeps
report-only benches isolated.
This commit also includes the first generated report:
- docs/report/1H-codesign-paper/ — main.tex + per-section .tex, figures,
toc.md contract, and the built 8-page main.pdf. Covers the platform
(source-level kernels, latency model + accuracy, HW config from
topology.yaml), GEMM via composite command, All-Reduce via PE_IPCQ, and
fused GQA combining both, plus discussion/conclusion/2H future work.
- scripts/paper/ — isolated report harnesses (not registered benches):
paper_gqa_latency.py harvests per-panel GQA end-to-end latency + engine
occupancy (the milestone only emitted op-counts); paper_plot_gqa.py
renders the GQA figures.
GEMM/All-Reduce reuse committed milestone figures/CSVs; GQA results are
generated fresh. Honest flags retained: PE_CPU dispatch cost is 0 in this
config, and the proposed two-composite softmax_merge decode is marked
designed-not-measured.
Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>
ywkang