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ywkang b715002b5a paper: §2 figure layout + Accuracy subsection + Table 1 → 2-col; §6 trim historical 4-panel content
§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>
2026-06-16 11:16:16 -07:00
ywkang 22f3968b51 paper(gqa): wire the 4-cases long-context decode comparison into §6
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>
2026-06-16 10:44:32 -07:00
ywkang e3f08972da paper: §2 polish + §5 fresh all-reduce data + kernbench probe table
§2 platform:
- Add a "memory-centric AHBM" sentence to the device-and-execution
  intro: each PE is paired with dedicated HBM bandwidth and on-PE
  TCM, so the performance question is about feeding compute from
  locally-attached memory + moving the unavoidable inter-PE traffic
  efficiently. Makes the AHBM character of the platform visible
  before §2.3 starts unpacking the latency model.
- Promote "Congestion and contention modeling" from \paragraph to
  \subsubsection: this is the platform's core differentiator over a
  peak-BW roofline, so it deserves its own heading.
- Rename "Control-plane (issue) cost model" to "Command dispatch
  overhead model" -- describes what it actually charges (the PE_CPU
  paying a fixed + per-byte cost to push a command to one of the
  accelerator engines) without the more abstract "control-plane"
  framing.
- Add a third Accuracy cross-check from kernbench probe: a
  PE→HBM DMA-distance sweep that confirms monotonic hop progression,
  bandwidth saturation matching the per-edge model, and the built-in
  invariants (D2H >= H2D, cross-CUBE best < worst). New
  Table~\ref{tab:probe-pe-dma} reports per-traversal latency and
  utilisation at 32KiB / 1MiB across five hop classes.
- Captured probe output as figures/probe_pe_dma_summary.txt for
  reproducibility.

§5 PE_IPCQ / all-reduce:
- Re-ran milestone-1h-ccl on current sim_engine (post-ADR-0064 Rev2
  and the IPCQ slot-wrap Phase-2 race fix). Updated the topology-
  comparison table and the buffer-kind caption to the fresh raw
  latencies. Headline ratios are preserved:
    torus vs mesh saving at 96 KB/PE: 24.8% (was 24.8%) -> ~25%
    torus vs ring saving at 96 KB/PE: 19.3% (was 19.3%) -> ~19%
    TCM vs HBM saving at 64 KB/PE: 13.4% (was 13.9%) -> ~13%
    TCM vs SRAM saving at 64 KB/PE: 37.2% (was 38.3%) -> ~37%
  The Executive Summary's "up to ~14%" / "up to ~38%" framing stays
  consistent with these post values.

Artifacts refreshed in src/kernbench/benches/1H_milestone_output/:
- ccl/summary.csv + per-topology PNGs + buffer-kind CSV/PNG
- ccl/comparison_mesh_vs_ring_vs_2DTorus_vs_theoretical_vs_fsim.png
- gemm/* (re-run yields identical pe_window structure; PNGs
  refreshed)

Paper figures synced to the fresh artifacts:
- figures/allreduce_comparison.png
- figures/allreduce_buffer_kind.png

Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>
2026-06-16 10:38:47 -07:00
mukesh 7c346dec1b paper(figures): GQA long-context decode 4-cases comparative figures
Generated by scripts/paper/paper_plot_gqa_decode_long_ctx_4cases.py
from the bench's sweep.json (S_kv=8192, the headline 128K run was
sidestepped — Case 2's single-PE 128-tile sweep is the long pole
and shape/ordering is preserved across scales).

  gqa_decode_long_ctx_4cases_latency.png   end-to-end latency / case
  gqa_decode_long_ctx_4cases_traffic.png   ipcq / dma op-count breakdown
  gqa_decode_long_ctx_4cases_memory.png    KV bytes per cube (slide-11)

Co-Authored-By: Claude Opus 4.7 <noreply@anthropic.com>
2026-06-15 17:48:34 -07:00
mukesh 1fbe833992 gqa(decode-4cases): wire latency + engine occupancy into sweep.json; add comparative plot script (5C.F)
Bench changes:
  - new _end_to_end_ns(op_log) and _engine_occupancy_ns(op_log) helpers
    in milestone_gqa_decode_long_ctx_4cases.py (mirror paper_gqa_latency.py)
  - _run_panel return dict now carries latency_ns + engine_occupancy_ns
    alongside op_log_summary, so sweep.json is the single source of truth
    for the comparative figures

Plot script:
  - new scripts/paper/paper_plot_gqa_decode_long_ctx_4cases.py reads
    sweep.json and emits 3 PNGs to docs/report/1H-codesign-paper/figures/:
      gqa_decode_long_ctx_4cases_latency.png   (end-to-end latency / case)
      gqa_decode_long_ctx_4cases_traffic.png   (ipcq/dma op counts / case)
      gqa_decode_long_ctx_4cases_memory.png    (KV bytes per cube / case)

Test changes:
  - 2 new tests verifying the helpers + _run_panel dict shape
  - lower smoke S_kv from 8192 -> 2048 (4x faster Case 2; assertions
    are S_kv-independent; one fold-loop iteration preserved)

18/18 tests pass in ~4 min.

Co-Authored-By: Claude Opus 4.7 <noreply@anthropic.com>
2026-06-15 17:45:44 -07:00
ywkang 7f437a20bd paper(platform): edit-pass through §2 KernBench Platform done
- Reordered §2 subsections to follow the SIP → CUBE → PE → graph
  flow: Why KernBench → Device and execution model → Latency model
  → Modeled hardware configuration. Readers now meet the device
  hierarchy before the graph abstraction that re-uses it.
- §2.2 Device and execution model: starts with the SIP/CUBE/PE
  hierarchy paragraphs (each anchoring fig:sip-arch, fig:cube-arch,
  fig:pe-arch); then the runtime-API/sim-engine/components bullet
  list; then the atomic-vs-composite command distinction (corrects
  the prior over-narrow framing that read every PE command as
  composite -- atomic single-engine commands exist too, and PE_CPU
  itself runs control-plane work directly).
- §2.3 Latency model: opens with the four-contribution decomposition
  (per-node overhead, per-edge transmission, drain, queuing delay)
  and the latency_model schematic; retains existing The hardware as
  a graph / From graph to DES / Latency contributions / Congestion
  / Control-plane cost model / Accuracy paragraphs. Accuracy
  paragraph now closes on KernBench's sufficiency for *relative*
  HW/SW design trade-offs given analytic + external-simulator
  agreement.
- New figures and assets:
  - figures/sip_architecture.pdf  (SIP-level graph view)
  - figures/cube_architecture.pdf (CUBE-level zoom-in)
  - figures/latency_model.png      (conceptual latency-model
                                   schematic with per-node /
                                   per-edge / drain / queuing-delay
                                   colour coding)
  - figures/pe_architecture.png    (carried over)
- Source-of-truth generator for the latency schematic:
  scripts/paper/paper_latency_model_diagram.py (a report-only
  harness under scripts/paper/ per the /paper isolation rule).
- main.tex preamble: \usepackage{tikz} added (kept from prior
  sequence-diagram draft -- harmless now that the latency model is
  a PNG; left in to keep paragraph numbering stable).

Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>
2026-06-15 17:17:19 -07:00
mukesh 756680f4e6 gqa: fold decode_long into the Case 4 kernel; drop 1D-chain dead code
Option B fold: the lrab math previously in
``_gqa_attention_decode_long.py`` (used only as a thin re-export by
the Case 4 wrapper and as the import source for ``_merge_running``
in Cases 1 / 3) now lives inline in the Case 4 kernel file. ``sub_w``
is hardcoded to 4 (the 4×2 cube sub-mesh geometry; root cube 6);
the legacy ``sub_w=0`` 1D-chain backward-compat path is removed
along with its dedicated tests — the dropped ``single_user_*`` /
``multi_user_*`` panels that exercised it are already gone.

Production changes:
  - inline lrab math into _gqa_attention_decode_long_ctx_cube_sp_pe_sp.py
    (drops sub_w param; _ROOT_CUBE=6 baked in)
  - inline _merge_running into Cases 1 (cube_sp_pe_tp) and 3
    (cube_repl_pe_sp) so they no longer depend on the deleted file
  - delete src/kernbench/benches/_gqa_attention_decode_long.py
  - remove dead _run_decode_panel / _DECODE_* constants /
    decode-side _PANEL_DISPATCH / _make_bench_fn decode branch
    from milestone_gqa_headline.py (only the prefill panel remains)
  - update _gqa_attention_decode_opt2.py docstring reference

Test changes:
  - delete 7 legacy test_gqa_*.py files that pre-dated the 4-cases
    architectural split (coverage now subsumed by the 16 4-cases tests)
  - remove test_opt2_matches_opt3_data_mode + _run_decode_data helper
    from test_gqa_decode_opt2.py (the parity check required sub_w=0
    which no longer exists; opt2's other 4 tests preserved)

20/20 tests pass (16 4-cases + 4 opt2 smoke/dispatch).

Co-Authored-By: Claude Opus 4.7 <noreply@anthropic.com>
2026-06-15 16:32:37 -07:00
mukesh ddee28a499 gqa(decode-4cases): rename bench/kernels/panels with long_ctx token
The 4-cases comparative study is specifically about long-context
decode (LLaMA-3.1-70B, S_kv=128K, T_q=1); the long_ctx token in the
names makes the scope explicit and aligns with the existing
_gqa_attention_decode_long convention.

Renames (mechanical; no semantic change):
  - bench file:   milestone_gqa_decode_4cases.py
                  → milestone_gqa_decode_long_ctx_4cases.py
  - bench name:   milestone-gqa-decode-4cases
                  → milestone-gqa-decode-long-ctx-4cases
  - output dir:   1H_milestone_output/gqa_decode_4cases/
                  → 1H_milestone_output/gqa_decode_long_ctx_4cases/
  - env vars:     GQA_DECODE_4CASES_RUN / _TOPOLOGY
                  → GQA_DECODE_LONG_CTX_4CASES_RUN / _TOPOLOGY
  - 4 kernel files _gqa_attention_decode_<case>.py
                  → _gqa_attention_decode_long_ctx_<case>.py
  - 4 kernel functions gqa_attention_decode_<case>_kernel
                  → gqa_attention_decode_long_ctx_<case>_kernel
  - 4 dispatch kinds  decode_<case> → decode_long_ctx_<case>
  - 4 panel names     single_kv_group_decode_gqa_<case>
                      → single_kv_group_decode_long_ctx_gqa_<case>
  - 4 helper functions _run_decode_panel_<case>
                       → _run_decode_panel_long_ctx_<case>
  - test file renamed in lockstep

Also: Case 4 smoke test now uses its case-specific helper
_run_decode_panel_long_ctx_cube_sp_pe_sp (consistent with Cases 1-3)
instead of the legacy _run_decode_panel from milestone_gqa_headline.
16 tests pass.

Co-Authored-By: Claude Opus 4.7 <noreply@anthropic.com>
2026-06-15 16:09:21 -07:00
mukesh 3c155be8e6 gqa(decode-4cases): give Case 4 its own thin kernel file for naming symmetry
Cases 1-3 each have a dedicated _gqa_attention_decode_<case>.py
kernel file; Case 4 previously reached into _gqa_attention_decode_long.py
via the headline bench's _run_decode_panel helper, breaking the
one-file-per-case convention. Adds _gqa_attention_decode_cube_sp_pe_sp.py
as a 20-line wrapper that bakes in sub_w=4 (the C=8 lrab geometry)
and gives Case 4 its own kind ("decode_cube_sp_pe_sp") and helper
(_run_decode_panel_cube_sp_pe_sp). decode_long.py is unchanged
(still serves the legacy decode_long tests). 16 tests pass.

Co-Authored-By: Claude Opus 4.7 <noreply@anthropic.com>
2026-06-15 15:58:11 -07:00
mukesh 0ef4fde5d8 gqa(decode-4cases): Case 1 — Cube-SP × PE-TP (inter-CUBE lrab only; PE-TP B=1 waste) (5C.A)
Adds the fourth and final 4-cases panel: KV split S_kv-wise across
the 8 cubes (cube=row_wise, S_local = S_kv/C), replicated within
each cube (pe=replicate). PE-TP at B=1 means only PE 0 of each cube
has work; PEs 1-7 early-return (slide-11 PE-TP-at-B=1 waste). No
intra-CUBE comm; inter-CUBE 8-way reduce reuses the lrab-adapted
center-root pattern (root cube 6) — same structural cost as Case 4's
inter-CUBE phase (21 ipcq_copy). 16 tests pass (4 per case).

Co-Authored-By: Claude Opus 4.7 <noreply@anthropic.com>
2026-06-15 15:30:00 -07:00
mukesh ae942f6959 gqa(decode-4cases): Case 3 — Cube-Repl × PE-SP (intra-CUBE AR only; 8× memory) (5C.C)
Adds the third 4-cases panel: KV replicated per cube (8× memory
waste), PEs SP on S_kv within each cube, intra-CUBE 8-way reduce on
(m, ℓ, O), and no inter-CUBE comm (every cube ends with full answer;
designated writer = cube 0). Reuses the row-chain + col-bridge
intra-CUBE pattern that anchors Case 4 (21 ipcq_copy per cube × 8
cubes = 168 total). 12 tests pass (4 Case 4 + 4 Case 2 + 4 Case 3).

Co-Authored-By: Claude Opus 4.7 <noreply@anthropic.com>
2026-06-15 15:18:41 -07:00
mukesh 5672c8f3ef gqa(decode-4cases): Case 2 — Cube-Repl × PE-TP (no comm; 8× memory) (5C.B)
Second case in the GQA decode 4-cases comparative study per
GQA_full_deck.pptx slide 11. Case 2 replicates K, V across all 8
cubes × 8 PEs (the slide-11 8 KB/tok/PE memory waste) and has zero
inter-rank comm. For B=1 (single-user decode default), only PE 0
of CUBE 0 has work — the inherent PE-TP waste slide 11 calls out.

Changes:
- New kernel: src/kernbench/benches/_gqa_attention_decode_cube_repl_pe_tp.py
  Simplest of the 4 cases. Active rank loads full Q/K/V from HBM,
  computes attention via S_kv tile sweep with online-softmax merge,
  writes O. All non-(0,0) ranks early-return. No tl.send/recv.
- src/kernbench/benches/milestone_gqa_decode_4cases.py:
    - Add panel single_kv_group_decode_gqa_cube_repl_pe_tp (Case 2)
      to _PANELS and _PANEL_DISPATCH.
    - Add _run_decode_panel_cube_repl_pe_tp helper: DPPolicy K/V/Q/O
      = cube=replicate, pe=replicate (models 8× memory waste).
    - Extend _make_bench_fn to dispatch kind="decode_cube_repl_pe_tp"
      to the new runner.
- tests/attention/test_milestone_gqa_decode_4cases.py:
    4 new tests assert Case 2 contract: panel registered, smoke
    completion, zero ipcq_copy (no comm), single dma_write from cube 0.

Verification: 8/8 tests pass (4 Case 4 anchor + 4 new Case 2).

Co-Authored-By: Claude Opus 4.7 <noreply@anthropic.com>
2026-06-15 14:59:58 -07:00
mukesh 65c365f858 bench(milestone-gqa-headline): drop misleading single_user_/multi_user_ panels
The legacy panel names suggested batched serving semantics they never
had — all four modeled a single user with KV sharded differently
(C=1 single-cube; C=4 multi-cube Cube-SP), at toy dims (T_q=4, S_kv≤128).
The single-KV-group C=8 panel + the new milestone-gqa-decode-4cases
bench cover the meaningful comparisons; pytest regression already
covers C=1/C=4 configurations end-to-end at richer scale.

Changes:
- milestone_gqa_headline.py: drop the 4 legacy panels; _PANELS now
  contains only single_kv_group_prefill_gqa_c8_p8. Update docstring.
- tests/attention/test_milestone_gqa_headline.py: drop the 3 legacy-
  panel architectural tests (Ring-KV traffic, root-only decode write,
  per-CUBE distributed output) and test_decode_panels_use_real_gqa
  (no decode panels in this bench anymore). Equivalent properties
  are asserted in test_milestone_gqa_single_kv_group_prefill_panel.py
  (64 dma_writes, 896 ipcq_copy) and test_milestone_gqa_decode_4cases.py
  (1 dma_write at cube 6, 189 ipcq_copy).
- tests/attention/test_milestone_gqa_single_kv_group_prefill_panel.py:
  drop test_existing_prefill_panel_runner_backward_compat (it exercised
  multi_user_prefill_gqa which no longer exists).
- scripts/paper/paper_plot_gqa.py: replace the 4 legacy _LABELS entries
  with the single single_kv_group_prefill_gqa_c8_p8 label.
- Regenerate 1H_milestone_output/gqa_headline/sweep.json from the new
  panel set.

Verification: 9/9 tests pass across the 3 affected test files.

Co-Authored-By: Claude Opus 4.7 <noreply@anthropic.com>
2026-06-15 14:50:25 -07:00
mukesh c164645aee gqa(decode-4cases): Case 4 anchor in dedicated bench (5C.D)
First milestone of the decode 4-cases comparative study per
GQA_full_deck.pptx slides 11-17. Case 4 (Cube-SP × PE-SP, the optimal
case per slide 11) is structurally the existing _gqa_attention_decode_long
at sub_w=4 (Increment 2's lrab-adapted center-root reduce). This commit
wires it into a dedicated bench so the remaining cases land alongside.

Changes:
- New bench: src/kernbench/benches/milestone_gqa_decode_4cases.py
  Houses the 4 case panels under one milestone-gqa-decode-4cases entry
  (gated by GQA_DECODE_4CASES_RUN=1; output to
   1H_milestone_output/gqa_decode_4cases/sweep.json). Cases 1-3 are
  TBD in subsequent sub-increments (5C.A/B/C).
- New panel: single_kv_group_decode_gqa_cube_sp_pe_sp
  C=8, P=8, sub_w=4, T_q=1, S_kv=131_072, d_head=128, h_q=8, h_kv=1.
- src/kernbench/benches/milestone_gqa_headline.py: _run_decode_panel
  extended with keyword-only sub_w/T_q/d_head/h_q/h_kv overrides
  (defaults preserve existing-panel behaviour).
- tests/attention/test_milestone_gqa_decode_4cases.py: 4 new tests
  asserting registration, smoke completion, reduce-to-root at the lrab
  center cube (cube 6), and the predicted 189-ipcq Case-4 traffic
  pattern (168 intra-CUBE + 21 inter-CUBE lrab Phase 1+2).
- tests/attention/test_milestone_gqa_headline.py: rename
  test_sweep_json_has_four_panels -> test_sweep_json_has_expected_panels
  and switch hardcoded 4 to len(PANELS) (the panel set grew to 5
  with Increment 5's single_kv_group_prefill_gqa_c8_p8).

Deviation noted: slide 13 prescribes AllReduce on (m,ℓ,O); our kernel
does reduce-to-root (only the lrab center cube has the answer) per
ADR-0060 §4. Treated as the kernbench Case-4 baseline.

Verification: all 4 new tests pass; 90 regression tests pass; the
previously-failing test_sweep_json_has_four_panels now passes under
its renamed form.

Co-Authored-By: Claude Opus 4.7 <noreply@anthropic.com>
2026-06-15 14:31:44 -07:00
mukesh 5b4d9cb597 bench(milestone-gqa-headline): scale single_kv_group prefill panel T_q=S_kv=1K (scratch budget)
The headline T_q=S_kv=32K target overflows the 1 MB per-PE scratch
pool: at T_q_local=4K and tile_s=1024 the scores matrix alone is 8 MB.
The prefill kernel's bootstrap section also leaves K_t/V_t/scores/
exp_scores persistent (outside tl.scratch_scope), inflating baseline.

Scale-down to T_q=S_kv=1K (T_q_local=128, fits comfortably) preserves
the C=8 + P=8 architecture demonstration; the true LLaMA 32K headline
awaits a future increment to add Q-axis tiling and tighten bootstrap
scratch discipline.

Verified end-to-end: kernbench run --bench milestone-gqa-headline now
produces sweep.json with all 5 panels. The new panel shows
ipcq_copy=896 (matches (C-1)·n_tiles·2·C·P = 7·1·2·8·8) and
dma_write=64 (one per PE, head-parallel + intra-CUBE PE-SP).

Co-Authored-By: Claude Opus 4.7 <noreply@anthropic.com>
2026-06-15 14:00:30 -07:00
mukesh 9e1242039b gqa: single-KV-group LLaMA-3.1-70B prefill milestone (Increments 1-5)
End-to-end wires C=8 P=8 d_head=128 prefill with snake-ring inter-CUBE
SFR, intra-CUBE PE-SP (all 64 ranks active), and the milestone bench
panel. Decode kernel gains lrab-adapted center-root reduce for the
2×4 sub-mesh per ADR-0060 §4.2.

Increment 1 — SFR multi-row snake
  src/kernbench/ccl/sfr_config.py: configure_sfr_intercube_ring gains
  submesh_shape / submesh_origin kwargs; installs a Hamiltonian snake
  ring through a rectangular sub-mesh (every hop is 1-hop physical
  neighbour). Backward-compat: 1D-row behaviour preserved when
  submesh_shape is None.
  tests/test_intercube_snake_ring.py (12 tests)

Increment 2 — Decode lrab-adapted center-root reduce
  src/kernbench/benches/_gqa_attention_decode_long.py: new sub_w param
  (default 0 = existing 1D-chain). sub_w >= 2 selects the ADR-0060
  §4.2 prescribed lrab-adapted Phase 1+2 reduce (bidirectional row +
  bidirectional col converge to the center cube), with log-sum-exp
  _merge_running replacing the plain + of lrab.
  tests/attention/test_gqa_decode_long_2d_reduce.py (4 tests)

Increment 3 — Prefill kernel at C=8 (no production change)
  Verified by inspection that the existing prefill_long kernel +
  Increment 1's snake SFR already work at C=8 without any kernel
  edit. The kernel speaks logical W/E; the snake routes it.
  tests/attention/test_gqa_prefill_long_c8_snake.py (3 tests)

Increment 4 — Intra-CUBE PE-SP in prefill (all 64 ranks)
  src/kernbench/benches/_gqa_attention_prefill_long.py: new P param
  (default 1 = existing PE-0-only). P > 1 splits T_q query-axis-wise
  across the P PEs of each CUBE; output rows are disjoint per PE so
  no intra-CUBE reduce is needed; each PE drives its own same-lane
  ring (P parallel rings).
  tests/attention/test_gqa_prefill_long_pe_sp.py (5 tests)

Increment 5 — LLaMA-scale milestone bench panel
  src/kernbench/benches/milestone_gqa_headline.py: new panel
  single_kv_group_prefill_gqa_c8_p8 (C=8, P=8, T_q=S_kv=32K,
  d_head=128). _run_prefill_panel extended with P/T_q/d_head
  defaults; routes snake SFR when C > mesh_w.
  tests/attention/test_milestone_gqa_single_kv_group_prefill_panel.py (3 tests)

Total: 4 production files modified, 5 new test files, 27 new tests.
Followed the Phase 1/2 protocol per CLAUDE.md throughout.

Co-Authored-By: Claude Opus 4.7 <noreply@anthropic.com>
2026-06-15 13:42:31 -07:00
ywkang 9270d3435a paper(platform): WIP — §2 KernBench Platform mid-edit
Mid-pass through §2. Captured progress so far:

- §2 intro previews the three new threads (graph view, DES engine,
  congestion) the rewritten latency section weaves together.
- §2.3 retitled to "Latency model: a graph traversed by events" and
  restructured into bold-led paragraphs:
  - The hardware as a graph (nodes = components, edges = links).
  - From graph to discrete-event simulation (node/edge events,
    deterministic ordering, correlation-ID trace).
  - Latency contributions (per-node fixed, per-edge size-aware,
    per-service occupancy).
  - Congestion: per-edge FIFO BW occupancy, HBM per-PC parallelism,
    component serial workers — the mechanisms that surface real
    bottlenecks instead of peak-BW roofline.
  - Control-plane cost model (FIXED + b·R) — unchanged.
  - Accuracy: extended with a second cross-check from the all-reduce
    study (torus vs. analytic startup-plus-per-packet model + FSIM
    external single-device reference). Existing GEMM analytic-vs-
    measured 10-20% check retained.
- §2.4 Hardware-configuration table unchanged.

Still TODO: cross-check accuracy numbers against a fresh
milestone-1h-gemm/ccl re-run; the current artifacts predate the
ADR-0064 Rev2 cost-model and IPCQ Phase-2 race fix and may need a
refresh before §2.3 final lock-in.

Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>
2026-06-11 16:31:42 -07:00
ywkang d5267ec718 paper(intro): edit-pass through §1 Introduction done
- §1 Introduction rewritten with AHBM-first opening, in-paper KernBench
  platform overview, GQA motivation and three architectural requirements,
  three matching HW-SW co-design mechanisms (GQA-aware placement,
  PE_IPCQ, composite-command GEMM under PE_SCHEDULER), broader-
  applicability outlook (PE_IPCQ as collective substrate, composite
  command for fused operator pipelines), and outline. Consistent with
  the Executive Summary structure.
- Executive Summary: extended broader-applicability closing with a
  forward-looking line previewing FFN/MoE integration.
- §5 section heading renamed from
  "All-Reduce Acceleration via PE_IPCQ" to
  "PE_IPCQ and Collective Communication".
- Title page date line refined to "2026 H1 Report".

Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>
2026-06-11 15:13:01 -07:00
ywkang a965db7056 paper(exec-summary): edit-pass through Executive Summary done
- Title: "Hardware-Software Codesign for Grouped-Query Attention on AHBM"
  (drop "Attention-Centric LLM Kernels" framing; subtitle pillars removed)
- Authors: Mukesh Garg, Jiyoon Lee, Yangwook Kang
- Affiliation: System Technology Group, AGI Computing Lab — 2026 1H
- Executive Summary rewritten into a tight three-paragraph structure:
  (1) GQA motivation + three AHBM architectural requirements (placement,
      inter-PE comm, pipelined memory-compute);
  (2) three matching HW-SW co-design mechanisms (GQA-aware placement,
      PE_IPCQ, composite-command GEMM under PE_SCHEDULER) and headline
      results (38% / 25-35% / 78%), closing on efficient HBM-bandwidth use;
  (3) broader applicability across the AHBM software stack.

Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>
2026-06-11 14:44:45 -07:00
ywkang 724a40453d test: fix 3 stale tests from the prior pull (registry list + memory_store msg)
test_bench_registry EXPECTED_NAMES: add the 3 milestone benches the pull registered (milestone-1h-ccl, milestone-1h-gemm, milestone-gqa-headline) — 11 benches, alphabetical. test_memory_store::test_shape_mismatch_raises: the pull made same-size reshapes byte-conserving (allowed) and an over-large read raise 'Out-of-bounds read' (not 'Shape mismatch') — match the new message. Full suite now 820 passed / 1 skipped / 0 failed.

Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>
2026-06-10 23:33:34 -07:00
ywkang 1a4ecb7aac gqa(ddd): DDD-0065 as-built content (prior commit only recorded the rename)
The reconciliation table, corrected file/test lists, measured 5.22x ratio, and the new section 15 (data-mode numerics D8 + N1-N4) — the content the git-mv in 30a0451 left uncommitted.

Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>
2026-06-10 23:27:43 -07:00
ywkang 30a0451481 gqa(ddd): DDD-0065 reconciled to as-built + promoted to docs/ddd/
Updated the detailed design to match the shipped implementation: an as-built reconciliation table (P1-first, pinned-based DMA, D7 hard-cap-error, D8 output handle, prologue 1-stage-tile feed, D6.7 prologue-scoped), corrected file/test lists, the measured 5.22x dispatch ratio, and a new section 15 documenting the data-mode numeric subsystem (D8 + N1-N4) the original DDD omitted. Status Draft->Accepted; moved docs/adr-proposed -> docs/ddd/.

Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>
2026-06-10 23:27:13 -07:00
ywkang f0c5b9c33f gqa(adr): ADR-0065 Proposed -> Accepted
Flat-ops CompositeCmd + softmax_merge recipe is fully implemented and tested: structural restructure (P1-P4), dispatch-cost measurement (P5b/P6, 5.22x per-tile win), and data-mode numerics (D8 output handle/space + N1-N4 composite GEMM / recipe MATH / accumulate / opt2 parity). git mv EN -> docs/adr/, KO -> docs/adr-ko/ (verify_adr_lang_pairs OK).

Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>
2026-06-10 23:16:52 -07:00
ywkang e9d62b908c gqa(adr-0065): N4 — opt2 numeric parity vs opt3 in data mode
composite() now awaits its prologue recipe operands (e.g. the score tile from a prior #1 composite) so the cross-composite RAW (#1 writes scores -> #2 reads them) is ordered: #2 waits for #1 before reading. With N1-N3, opt2 (the two-composite recipe kernel) now computes a correct attention output end-to-end in data mode and matches opt3 within fp tolerance.

Scope note: the e2e opt2<->opt3 parity holds in the near-uniform-attention regime (small inputs). kernbench's K reshape-as-transpose (opt3 kernel docstring: 'correct for zero/symmetric inputs') makes opt2's per-sub-tile K interpretation differ from opt3's single-tile one for high-contrast inputs — a pre-existing kernbench limitation shared by both kernels, not the recipe. The EXACT recipe math (online-softmax merge m/l + O = O*corr + P@V) is verified non-trivially and exactly by N2/N3 (test_recipe_data_mode.py). Suite 817 pass / 3 pre-existing fail.

Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>
2026-06-10 23:13:16 -07:00
ywkang 5bbe293bea gqa(adr-0065): N3 — GEMM-epilogue accumulate dataflow (O = O.corr + P.V)
Two fixes make the recipe's P.V GEMM fold into the rescaled accumulator: (1) op_log marks the composite gemm record accumulate=True when an 'add' epilogue targets the GEMM's own output; data_executor._execute_gemm then does O = O_existing + a@b instead of overwriting. (2) PE_SCHEDULER records the composite's numeric op at COMPLETION (in _retire_on_done) instead of at dispatch, so the GEMM's t_start sorts AFTER its prologue MATH ops -> it reads the computed P and the rescaled O.

Verified end-to-end (DataExecutor): the full recipe produces O = O_old*corr + P@V matching a numpy flash-attention reference. Suite 816 pass / 3 pre-existing fail.

Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>
2026-06-10 23:06:01 -07:00
ywkang 3d4a3d43c4 gqa(adr-0065): N2 — softmax_merge recipe MATH ops compute in data mode
data_executor._compute_math gains the 5 recipe ops (rmax/rsum as keepdims reductions, max_elem/exp_diff/mul_bcast as binary; numpy broadcasting covers bcast_axis). tiling._math_stage now carries operand+output addrs/shapes/spaces + axis on the recipe prologue MATH stages. op_log.record_end promotes a MATH stage to op_kind='math' ONLY when it carries input_addrs -> the DataExecutor runs it; legacy epilogue MATH stages (bias/relu, no addrs) stay op_kind-opaque -> byte-equal.

Fixed a latent P2 lowering bug exposed by data mode: _resolve_recipe_dst gave reductions shape (G,) (axis removed) but max_elem broadcasts them against the running m=(G,1); reductions now keep the reduced axis as size 1 (keepdims) -> (G,1). Verified end-to-end: running the recipe's 8 MATH ops through the DataExecutor produces m, l (fully updated online-softmax) and O (rescaled by corr) matching a numpy reference. Suite 815 pass / 3 pre-existing fail.

Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>
2026-06-10 22:56:25 -07:00
ywkang 4089e18770 gqa(adr-0065): N1 — composite GEMM computes numerically in data mode
Two changes make a composite's matmul replay in Phase 2: (1) op_log _extract_op_info(CompositeCmd) now SCANS ops for the gemm op (it is ops[0] for a legacy composite but sits after the prologue MATH ops in a recipe), emitting one composite_gemm record with the gemm's a/b/out addrs+spaces; (2) PE_SCHEDULER._dispatch_composite records the composite as a zero-duration numeric op (no-op without an op_logger, so latency-only mode is unchanged). Verified: a composite GEMM with seeded inputs writes a@b to its HBM output.

DataExecutor._execute_gemm is now best-effort: if an operand's data was never produced (torch.empty bench input) or a shard read is out-of-bounds (column-wise sharded operand read at full shape), skip the matmul instead of crashing. This keeps composite-using benches (qkv-gemm, composite-epilogue) green now that their previously-uncomputed GEMM actually fires. Suite 813 pass / 3 pre-existing fail.

Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>
2026-06-10 22:46:39 -07:00
ywkang e8d6c283d8 gqa(adr-0065): D8 — composite returns output handle + output-space DMA
tl.composite now returns the output TensorHandle (not a CompletionHandle) so its result chains like tl.dot's; the handle carries the completion in a CompositeFuture pending so downstream ops and tl.wait auto-await it. out is a handle: out=tl.ref(addr,shape) (HBM, DMA_WRITE inside the composite) or an in-place TCM handle (STORE only); omitted -> TLContext auto-allocates a TCM scratch. out_ptr kept as HBM shorthand (= out=tl.ref(out_ptr, shape)) to avoid churning ~30 existing call sites.

tl.ref now returns space=hbm (it references HBM data; operand-input DMA stays pinned-based per D4 so input streaming is unchanged). tiling: the tile loop's DMA_WRITE is gated on out.space==hbm (out analog of the operand pinned rule) — a TCM output stays on-chip (chainable) and its high-bit scratch address no longer hits the DMA PA decoder.

Fixes the opt2 data-mode crash: the recipe accumulator O is TCM -> no DMA_WRITE -> opt2 now RUNS end-to-end in data mode (enable_data=True). Numeric parity of the recipe MATH ops is the next step. Suite 812 pass / 3 pre-existing fail; existing composite benches use out_ptr->hbm->DMA_WRITE unchanged (byte-equal).

Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>
2026-06-10 22:29:10 -07:00
ywkang dd525bfcb7 paper: add /paper skill + 1H HW-SW codesign report (GEMM, All-Reduce, fused GQA)
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>
2026-06-10 22:15:14 -07:00
ywkang 4a55ae5c0b gqa(adr-0065): P6 — close dispatch-ratio loop (ADR-0064 Test #9 direction)
Extend the opt2 R-sensitivity test to assert the opt3/opt2 dispatch ratio increases as R decreases (4.20x -> 5.22x -> 5.45x at R=0.25/0.0625/0.03125) — the cost is FIXED-dominated (command-count-driven), per ADR-0064 Test #9. Test-only; no production change (the P0 cost model + P2 recipe already make the ratio measurable).

Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>
2026-06-10 21:04:45 -07:00
ywkang 35453cc4fe gqa(adr-0065): P5(B) — decode opt2 two-composite kernel + dispatch measurement
New _gqa_attention_decode_opt2.py: per-tile attention as #1 Q.Kt GEMM composite + #2 softmax_merge recipe composite (online merge + P.V + add). Runnable in op_log mode; full data-mode numeric parity is a deferred follow-up (P5-numerics).

Measured per-tile PE_CPU dispatch (ADR-0064 Rev2 default): opt3=960ns vs opt2=184ns = 5.22x (gate >2x), FIXED-dominated (command-count reduction) — the ADR-0060/0064 CPU-offload win. opt2<opt3 across R in {0.25,0.0625,0.03125}. K-before-V: softmax_merge prologue carries no DMA; V (ref) streams only in the GEMM tile loop.

Fix latent P3 bug surfaced by the first e2e recipe run: prologue MATH stages were FOLDED into the first GEMM tile, but a folded MATH->DMA_READ boundary needs a PE_MATH->PE_DMA token route the pipeline never wires (KeyError pe_dma). Now prologue/post-loop stages are fed as standalone 1-stage tiles (each completes on its component); completion count includes them. Existing benches have no prologue -> tiles + feed order unchanged (byte-equal); full suite 806 pass / 3 pre-existing fail.

Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>
2026-06-10 21:02:27 -07:00
ywkang 17fb94086e gqa(adr-0065): P4 — strict-FIFO RW hazard tracker
_RwHazardTracker (pe_scheduler): a composite registers its write set (rw_handles) as in-flight; a new composite whose read (op operands) or write handles intersect an in-flight write set waits on those composites' done events before admission (ADR-0065 D6.3 / DDD 8). _dispatch_composite calls admit() before feeding and retires on the done event.

Legacy composites (rw_handles=()) never register and never block -> existing benches untouched (byte-equal). Strict FIFO is conservative (partial overlap waits for full drain); RW-aware reorder is deferred (A4).

Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>
2026-06-10 20:36:31 -07:00
ywkang 55f025c4b1 gqa(adr-0065): P3 — flat-ops PE_SCHEDULER plan (position-scan + prologue stages)
tiling.generate_plan_from_ops: scan flat ops for the GEMM (<=1); pre-GEMM KERNEL ops become single-shot prologue MATH stages, post-GEMM ops split by scope (K_TILE/OUTPUT_TILE epilogue + KERNEL post-loop). MATH-only composite reproduces the legacy math-head plan. Prologue/post-loop stages fold into the first/last tile so the feeder + completion counting are untouched (existing benches have neither -> byte-equal op_log).

PipelinePlan gains prologue_stages/epilogue_stages. pe_scheduler._generate_plan delegates to generate_plan_from_ops. DMA keeps the existing pinned signal (NOT a space flip); recipe scratch/primary-out handles are pinned=True so the head GEMM's auto-bound a (=P) is consumed in place.

ADR-0065 D4/D6.7/Test#5 amended (EN+KO): DMA decision from pinned, not space; prologue recipe ops TCM-only (head op exempt -- it may stream from HBM).

Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>
2026-06-10 20:24:33 -07:00
ywkang 184f654295 gqa(adr-0065): P2 — softmax_merge recipe + TLContext prologue lowering
New triton_emu/tl_recipes.py: RecipeDescriptor/EngineOp/PrimaryOutSpec + RECIPE_DESCRIPTORS['softmax_merge'] (8-step engine_seq). PE_SCHEDULER does not import it (ADR-0065 D5 boundary).

TLContext.composite(): add prologue=[...] + out=TensorHandle kwargs, a optional. _expand_prologue lowers a recipe into flat MATH OpSpecs (scope=KERNEL), allocates TCM scratch, derives the primary-out slot 'P' and auto-binds it into the head GEMM a (D6.6 conflict check); rw_handles=(m,l,O). decode-opt2 #2 lowers to 10 ops [rmax,max_elem,exp_diff,exp_diff,rsum,fma,mul_bcast,copy,gemm,add].

D6.7 (MATH operand TCM-only) scoped to prologue recipe ops only — the head op (gemm or math) keeps existing DMA-staged-from-HBM behavior. D6.1 (GEMM count <=1) on the whole composite. Host-side lowering only; PE_SCHEDULER position-scan is P3.

Also commit the ADR-0064 Rev2 promotion content that the prior commit's git mv dropped: Status Proposed->Accepted + D7 amended to hard-cap ValueError (no segmentation), EN+KO.

Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>
2026-06-10 19:48:29 -07:00
ywkang 47e2c78c66 gqa(adr-0064/0065): flat-ops CompositeCmd (P1) + structural dispatch cost (ADR-0064 Rev2); promote ADR-0064
ADR-0065 P1: CompositeCmd -> flat ordered ops list (drop legacy op/a/b/out_addr fields); OpSpec.operands dict + out handle. Meaning-preserving (op_log byte-equal); pe_scheduler + op_log read the head op.

ADR-0064 Rev2: replace Rev1 per-op cost table with structural FIXED + logical_bytes*R formula. logical_bytes on every PeCommand; new common/pe_cost_model.py; cost centralized in TLContext._emit (load/recv_async charge explicitly); pe_cpu/kernel_runner wire the per-PE model + clock. D7: cap exceeded -> ValueError (no auto-segmentation). Remove Rev1 cpu_issue_cost.py + its tests. No goldens churn.

Promote ADR-0064 Rev2 Proposed->Accepted (docs/adr/ + docs/adr-ko/); amend D7 (error not segmentation) + record P1-before-P0 ordering in ADR-0064/0065 Migration notes (EN+KO).

Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>
2026-06-10 19:18:04 -07:00
mukesh 79ddb12b42 gqa: explain why Tile-0 / bootstrap can't be folded into the tile loop
Comment-only change. Adds a kernbench-only limitation note at the
Tile-0 / bootstrap block in all four GQA attention kernels:

  - persistent (m, l, O) must live outside tl.scratch_scope so
    subsequent tiles' merges can read them;
  - kernbench has no scratch-backed initializer (tl.zeros / tl.full
    return addr=0 handles), so we can't seed (-inf, 0, 0) and rely
    on tl.copy_to;
  - therefore Tile 0 must compute the initial running state directly.

prefill_long adds a third bullet noting the ring-step ordering reason
(k=0 must send W before any k>0 can recv E, so the (t=0, k=0) step has
to run outside the scoped loop where the send is conditional on C > 1).

Each block also notes that a real Triton port collapses Tile 0 into a
unified loop (SSA tensors stay live across iterations).

No behavior change; tests unchanged.

Co-Authored-By: Claude Opus 4.7 <noreply@anthropic.com>
2026-06-10 16:35:43 -07:00
ywkang 3647e2d8f5 gqa(adr): ADR-0064/0065 second-pass review — 1024B rationale, FIFO as ordering source, robust formula-based tests, D5/D6 auto-bind alignment
ADR-0064 Revision 2 second-pass review fixes:
- D7 added 1024-byte cap rationale: explicitly framed as a *safe
  engineering limit* (intentionally above all known composites at ~322
  bytes, finite descriptor capacity placeholder), not a measured HW
  number. Default is the discipline; topology override for real HW.
- D7 segment ordering: strict FIFO is the *ordering source*; rw_handles
  is dependency metadata, not the ordering primitive. Explicit note for
  the future RW-aware reorder migration path.
- Tests rewritten around the formula (D1) instead of specific numbers:
  - Test #1 → "formula preservation" (parametrized across composites,
    asserts dispatch == FIXED + bytes × R, not anchor 43 ns).
  - Test #2 → robust "opt3 > 2 × opt2" qualitative gate; ≈ 4.0× is
    informative only, not the gate, so calibration changes don't break.
  - Test #9 → qualitative (opt2 < opt3 at all R), not a numeric ratio.
- Anchor description in D3 stays as *informative* (shows the model
  produces ≈ 43 ns at defaults), but is no longer a test gate.

ADR-0065 second-pass review:
- D5 step 5 aligned with D6.6 invariant: explicit conflict check before
  auto-binding (previously written as if auto-bind always happens).
  Mirrors D6.6 wording: error if both kernel explicit `a` and prologue
  primary_out are present.
- Test #7 made robust: `opt3 > 2 × opt2` gate (was ≈ 4.0×).
  Default-calibration model expectation (≈ 4.0×) recorded as informative
  reference, not the gate.

DDD-0065 follow-on robust thresholds:
- §1.4 success criteria: ratio condition rewritten as `opt3 > 2 × opt2`
  with model-expected ≈ 4.0× as informative.
- §9 P6 phase gate: `opt3 > 2 × opt2` (was 4.0× ± 15%).
- §10 dispatch ratio test: assert `opt3 > 2 × opt2`; record observed
  ratio for performance tracking but do not gate on it.

Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>
2026-06-10 16:34:34 -07:00
ywkang a8d04750e6 gqa(adr): ADR-0065 review fixes — KERNEL phase/repetition split, auto-bind conflict + MATH-TCM invariants, FIFO conservatism note, logical_bytes per-op summation
ADR-0065 review fixes:
- D3 semantics clarified: position determines *phase* (pre-loop / head /
  in-accumulation / per-output-tile / post-loop), scope determines
  *repetition*. KERNEL = "once per CompositeCmd invocation", not "once
  per kernel launch" — removes ambiguity around softmax_merge's KERNEL
  scope at different positions before/after GEMM.
- D4 MATH-TCM invariant: Phase 1 limits DMA auto-insertion to GEMM
  operands and head outputs; MATH operand with space="hbm" raises
  validation error at TLContext emit. Catches kernel misuse early; a
  MATH-with-HBM path is future work (explicit tl.load + MATH composite).
- D6 #6 NEW: auto-bind conflict — explicit GEMM `a=` + prologue
  primary_out simultaneously → validation error (prevents "which value
  wins" ambiguity).
- D6 #7 NEW: MATH operand TCM-only restatement.
- Consequences/Negative: strict-FIFO conservatism note — safe but may
  under-expose composite-level overlap when handle-sharing composites
  could in principle run in parallel.
- Test Requirements #10, #11: auto-bind conflict + MATH-HBM validation
  error tests.

ADR-0064 Revision 2 clarification:
- D2 counting rule: per-op summation, no deduplication. Same handle
  appearing in multiple OpSpecs or in rw_handles is counted
  independently — matches HW reality (each descriptor field is a
  distinct address slot, rw_handles is separate metadata block).
  Example walked through (mul_bcast with O in src_a + out + rw_handles).

DDD-0065 follow-on:
- §3.2: new test file test_tl_composite_validation.py covers auto-bind
  conflict, MATH-TCM, GEMM-count invariants.
- §4.3: phase vs repetition split aligned with ADR-0065 D3.
- §6 lowering pipeline: step 5 adds auto-bind conflict check; step 8
  NEW — operand space validation; step 9 (size cap); step 10 (emit).
- §8 strict-FIFO conservatism note: explains why next-tile #1 cross-tile
  pipelining still works under FIFO (no rw overlap), and where the
  conservatism would hurt (future handle-sharing recipes).
- §10 verification: invariant-guard tests (auto-bind conflict, MATH
  TCM, per-op summation accuracy).

Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>
2026-06-10 16:29:39 -07:00
ywkang 95cecccd8e gqa(adr): ADR-0064/0065 review fixes — composite size cap, type-aware logical_bytes, R recalibration
ADR-0064 Revision 2 review fixes:
- D7 NEW: composite size cap (MAX_COMPOSITE_LOGICAL_BYTES default 1024
  bytes). Oversized recipes deterministically segmented into N
  CompositeCmds; each segment incurs its own dispatch cost. Models real
  HW limits (descriptor queue entry, scheduler parser buffer, command
  SRAM) and prevents the model from rewarding pathologically-large
  fused composites.
- D2: type-aware extra-field byte counting (int/float=4, bool=1,
  tuple/list=1+4N, str=1) — replaces uniform 4 bytes per extra.
- D3: recalibrated defaults to FIXED=40 cycles, R=0.0625 cycles/byte
  (16 B/cycle — typical on-die descriptor queue width); anchor stays at
  ~43 ns for typical 1-OpSpec composite. Clarified anchor description:
  DMA stages do not appear in logical_bytes (auto-inserted by
  PE_SCHEDULER from operand.space per ADR-0065 D4).
- D4: removed clock_freq_ghz from pe_cost_model: override block;
  conversion uses the PE node's existing clock_freq_ghz attr. Added
  max_composite_logical_bytes knob.
- Context: emphasized command-count reduction (FIXED) as the primary
  signal; byte term as secondary refinement.
- Open review: added large-composite scheduler-cost stress test.
- Test req: added composite-size-cap (#8) and R-sensitivity sweep (#9).

ADR-0065 + DDD-0065 follow-on updates:
- opt2 vs opt3 dispatch ratio updated 2.4× → ≈4.0× under new defaults
  (FIXED-dominated, reflecting the corrected framing).
- Test req #9: decode opt2 composite fits within 1024-byte cap; no
  segmentation needed for the GQA workload.
- DDD §6: TLContext lowering checks logical_bytes against cap (step 8).
- DDD §11: performance model recomputed with new defaults + sensitivity
  table across R ∈ {0.25, 0.0625, 0.03125} confirming opt2 < opt3 holds.
- DDD §9 P6 gate: ratio band 2.4×±10% → 4.0×±15%; sensitivity sweep added.

Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>
2026-06-10 16:21:58 -07:00
mukesh 7fad0371c5 gqa: tile-granular Ring KV (P3c) + rename to gqa_attention_* + ADR-0060/62/63/64 → Accepted
Three logically distinct changes, bundled for atomic test green:

1. **P3c — prefill_long tile-granular Ring KV** (ADR-0060 §5.5.1 amendment).
   Convert the ring from slice-granular (one full ``(d_head, S_local)``
   KV slice per step) to tile-granular (``n_tiles`` tiles of
   ``TILE_S_KV`` per step). Nested loop with outer tile, inner ring step:
   each tile propagates through all C ring positions before the next
   tile starts, so IPCQ in-flight depth stays at 1 per direction.
   Bootstrap at ``(t=0, k=0)`` outside the scratch_scope establishes the
   persistent ``(m, ℓ, O)``; every other iteration scope-wraps + persists
   via ``copy_to``. Per-rank persistent scratch shrinks to ~1 KB; per-tile
   scope bounded by TILE_S_KV regardless of S_local. Headline:
   prefill_long now completes at S_kv=128K (previously overflowed).
   New: ``tests/attention/test_gqa_prefill_long_tile_ring.py``
   (3 tests — ceiling-lift + tile-granular ipcq_copy count +
   per-CUBE distributed output regression guard).

2. **Rename ``gqa_*`` → ``gqa_attention_*``** across kernel files,
   function names, and importers. The "attention" name makes the role
   explicit (GQA is grouped-query attention) and matches upstream Triton
   FlashAttention naming conventions. Renames:
     _gqa_decode_long.py        -> _gqa_attention_decode_long.py
     _gqa_decode_short.py       -> _gqa_attention_decode_short.py
     _gqa_prefill_long.py       -> _gqa_attention_prefill_long.py
     _gqa_prefill_short.py      -> _gqa_attention_prefill_short.py
   And function names ``gqa_<phase>_<context>_kernel`` →
   ``gqa_attention_<phase>_<context>_kernel``. Updated 1 bench file
   (milestone_gqa_headline.py) and 10 test files.

3. **ADR-0060 / 0062 / 0063 / 0064: Proposed → Accepted**.
   All four are reflected in production code and covered by tests:
   - ADR-0060 (GQA fused attention): 4 kernels deployed; §5.5.1
     amendment added for the tile-granular Ring KV introduced by P3c
     (EN + KO mirror).
   - ADR-0062 (lazy tl.load): LoadFuture + _await_pending live in
     tl_context.py.
   - ADR-0063 (tl.scratch_scope + tl.copy_to): used in every chain
     reduce + tile sweep + ring step. EN-only previously; KO
     translation authored as part of this commit (CLAUDE.md
     bidirectional rule).
   - ADR-0064 (per-op-type CPU issue cost): cpu_issue_cost.py +
     issue_cost_table wiring in tl_context.py (Phase E).
   Files git mv'd from docs/adr-proposed/ to docs/adr/ (EN) and
   docs/adr-ko/ (KO). ADR-0061 (tl.broadcast) stays Proposed — no
   implementation; documented as optional convenience primitive in
   the ADR itself.

Tests: 88/88 focused regression green
(tests/attention/ + Phase E + TL discipline).
ADR pair verification: ``python tools/verify_adr_lang_pairs.py`` OK.

Co-Authored-By: Claude Opus 4.7 <noreply@anthropic.com>
2026-06-10 16:20:00 -07:00
ywkang a8c50238c6 gqa(adr): ADR-0064 Rev2 (structural dispatch cost) + ADR-0065/DDD-0065 (flat-ops composite + softmax_merge recipe)
ADR-0064 Revision 2: replace per-op-type calibration table with a
structural formula `FIXED_PER_CMD + cmd.logical_bytes × R`, defaults
anchored at typical composite ≈ 45 ns. Topology yaml override under
`pe_cost_model:` block; logical_bytes property per PE command.

ADR-0065: implement ADR-0060 §5.6 / §8 item 4 carve-out as a flat-ops
CompositeCmd (no head/epilogue structural fields — position + scope
drives placement) + first stateful recipe `softmax_merge` (MATH-only
8-step). RECIPE_DESCRIPTORS lives in TLContext-adjacent module only;
PE_SCHEDULER stays recipe-free and auto-inserts DMAs from operand
`space`. Strict-FIFO RW hazard tracker; ≤1 GEMM per composite
invariant. User-facing `tl.composite(prologue=[...], op=, epilogue=[...])`
API preserved; existing benches unchanged (meaning-preserving refactor).

DDD-0065: implementation-ready phased plan (P0=ADR-0064 Rev2 first,
P1-P6 for ADR-0065), file plan, recipe engine sequence, scheduler
plan-gen algorithm, RW tracker design, test matrix.

Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>
2026-06-10 16:11:20 -07:00
mukesh 91cdfebb67 gqa: S_kv tile sweep for decode_long/decode_short/prefill_short (ADR-0063 §A.2)
Replace each kernel's local one-shot partial with a Tile-0 bootstrap + a
``scratch_scope``-wrapped merge loop. Per-rank scratch is now bounded by
``TILE_S_KV = 1024`` regardless of ``S_local``, lifting the long-context S
ceiling. Backward compatible at ``S_local <= TILE_S_KV`` (loop body is
empty; op_log structurally identical to today).

Framework: extend ``memory_store.read`` to support partial reads at
offsets within a stored region. Models real Triton ``tl.load(ptr+offset,
shape=...)`` — needed because each tile loads ``k_ptr + tile_start*row_bytes``
for its sub-slice of the per-rank KV region.

prefill_long is intentionally left untiled. Its ring loop carries
full-slice ``Kc``/``Vc`` for ``tl.send`` between CUBEs, so tile-sweeping
step 0 wouldn't shrink the kernel's actual scratch footprint. Lifting
prefill_long's ceiling requires a tile-granular ring rewrite — separate
phase. Docstring + inline comments cleaned to reflect the current shape.

Docstrings across all 4 GQA kernels: drop P1a/P2a/P2b/P6a/P6b lineage
paragraphs and historical deviation lists; describe each kernel by what
it does, not how it got here. Add explicit ``# Local attention`` /
``# Communication`` section headers.

Tests: new ``tests/attention/test_gqa_tile_sweep.py`` with 5 tests
covering single-tile op_log stability, multi-tile ``copy_to`` emission
across all 3 refactored kernels, and the headline ceiling-lift
(decode_long at S_kv=256K). Full focused regression green: 85/85 across
``tests/attention/`` + Phase E + TL discipline tests.

Co-Authored-By: Claude Opus 4.7 <noreply@anthropic.com>
2026-06-10 15:33:29 -07:00
mukesh 5a76ed4f6a gqa: rename long-context kernels to *_long for symmetry with *_short
Make the file + function naming symmetric:
  _gqa_decode.py        -> _gqa_decode_long.py
  _gqa_prefill.py       -> _gqa_prefill_long.py
  gqa_decode_kernel     -> gqa_decode_long_kernel
  gqa_prefill_kernel    -> gqa_prefill_long_kernel

Mirrors the existing _gqa_{decode,prefill}_short.py naming. Updates the
two imports + two call sites in milestone_gqa_headline.py and the 9
attention tests that import the kernels.

Tests: 72/72 focused regression green (tests/attention/ + Phase E + TL
discipline). milestone-gqa-headline bench passes its 7 panel/schema
assertions.

Co-Authored-By: Claude Opus 4.7 <noreply@anthropic.com>
2026-06-10 10:05:54 -07:00
mukesh d282144339 gqa: ADR-0060/0062/0063/0064 unified GQA kernels + CPU cost model
Land the new GQA fused-attention kernels (ADR-0060) for prefill/decode
across long and short context, the TL discipline primitives they depend
on (ADR-0062 lazy load, ADR-0063 scratch_scope + copy_to), and the
per-op-type CPU issue cost model (ADR-0064). Remove the pre-ADR-0060
mesh-attention baseline now that the unified kernels supersede it.

ADR-0060 (long context)
- _gqa_decode.py: M-fold + 2-level chain reduce-to-root (Level-2
  intra-CUBE row-then-col + Level-1 inter-CUBE) — root-only output.
- _gqa_prefill.py: head-parallel + Ring KV rotation around C CUBEs,
  online-softmax merge per ring step, per-CUBE distributed output.
- Each merge stage wraps in scratch_scope() and persists running
  (m, l, O) via copy_to() to lift the 1 MiB scratch ceiling.

ADR-0060 §B.split.2 (short context, kv_per_cube in {1,2,4,8})
- _gqa_decode_short.py / _gqa_prefill_short.py: no cube-SP; each CUBE
  owns whole KV heads; PE-parallel heads with intra-group chain
  reduce. Prefill has no Ring KV (each head fully resident).

ADR-0062 (lazy tl.load): future-bearing TensorHandle, auto-wait at
first consuming op (dot/MATH/store/send/copy_to/composite).

ADR-0063 (tl.scratch_scope + tl.copy_to): scoped per-tile arena with
copy_to writeback primitive for persistent running state.

ADR-0064 (CPU issue cost model)
- common/cpu_issue_cost.py: per-op-type table (composite=40 ns,
  primitives=5 ns); ratios are load-bearing per D1.
- TLContext: issue_cost_table param; _emit_dispatch_overhead(kind)
  consults table with dispatch_cycles fallback (ADR-0046 §D6
  back-compat).
- Live PE_CPU paths (greenlet + legacy) construct TLContext with
  DEFAULT_CPU_ISSUE_COST so saturation lever (ADR-0060 §1) is
  measurable end-to-end.

P7 headline bench: milestone-gqa-headline writes per-panel
op_log_summary to 1H_milestone_output/gqa_headline/sweep.json. No
figure renderers yet (deferred).

Removals (pre-ADR-0060 baseline now superseded):
- benches: _attention_mesh_kv.py, _attention_mesh_mlo.py,
  _attention_mesh_mlo_2d.py, milestone_gqa_llama70b.py
- tests: test_attention_*, test_mesh_*, test_milestone_gqa_llama70b
- topology: llama70b_4sip.yaml (only consumer was the deleted diag)
- artifacts: 1H_milestone_output/gqa/ (sweep.json + 5 PNGs)
- tests/gqa/ plot helper + test (broken on Windows Tcl/Tkinter)
- ADR-0060/0061 references to deleted file paths cleaned up
  (EN + KO kept in sync).

Tests: 124/124 focused regression green (attention + Phase E + TL
discipline + triton_emu + pe_components). Full regression: 764 pass,
2 pre-existing test_bench_registry failures (stale EXPECTED_NAMES
across multiple benches, not introduced here).

Co-Authored-By: Claude Opus 4.7 <noreply@anthropic.com>
2026-06-09 18:15:59 -07:00
mukesh b3730a33eb policy(adr): ADR-0026 Revision 6 — document DPPolicy.cube_start
Amends ADR-0026 to reflect the cube_start field added in e2fe331.
The production code shipped without an ADR update; this fills that
gap. Documentation-only change (no production code, no test code).

Changes (mirrored in both EN and KO):
- Status: Revision 5 → Revision 6
- D1: add ``cube_start: int = 0`` to the canonical DPPolicy dataclass
- D3: ``cube = policy.cube_start + cube_id`` in resolve_dp_policy
- D8: new section explaining purpose (disjoint cube sub-meshes for
      GQA Llama-70B 8-KV-group headline), semantics, default-0 backward
      compatibility, intra-device constraint, design rationale
      (scalar vs 2D origin vs cube_ids list), and the kernel-side
      cube_start subtraction needed to compensate for ADR-0022's
      physical-cube-id ``program_id(axis=1)`` semantics.

tools/verify_adr_lang_pairs.py passes (EN/KO Status keyword and
title in sync).

Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>
2026-06-08 14:18:27 -07:00
ywkang ab324c155c gqa(adr): review fixes — unify KV placement to contiguous, ring/reduce cost model, opt3 wording, rank def
Per review:
- Placement unified to *contiguous* C×P blocks throughout (S0/S2.1/S2.2/S0.5);
  round-robin demoted to the rejected alternative. Adds driver SP-enable
  threshold fallback (smaller C / C=P=1 for short/early decode).
- Ring-vs-reduce cost model in S5.5: reduce ~ G*T_q*log(C*P) (O dominant;
  m,l scalars), ring ~ 2*S (total K+V bytes a CUBE injects over C-1
  rotations; recv_async pipelines so latency ~ max-step) -> ring wins when
  T_q > 2S/(G*log(C*P)).
- opt3 'removes the bubble' -> 'hides (subject to scheduler+engine balance)'
  everywhere; table 'hidden*' with footnote.
- 'rank' defined (SP participant = a PE in a CUBE, KV shard in its HBM->TCM).
- out-proj handoff contract (S0.5.4); S11 gate-type note (absolute latency
  deferred to ADR-0064; structural + relative-to-baseline gates now).
- greenlet-as-contrast tightened to 'primitive-op (tl.dot) path' (S1, SB).
KO mirror synced; DDD gets the SP-enable threshold fallback. Docs only.

Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>
2026-06-05 00:52:38 -07:00
ywkang 9103661098 gqa(adr): mark DDD-0060 as synced in ADR-0060 SB (EN+KO)
DDD-0060 was rewritten to the two-kernel composite-hybrid design, so SB
item 1 ('DDD not yet synced') is stale. Update EN + KO mirror to record the
DDD as synced (ADR authoritative, DDD = impl how-to). Docs only.

Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>
2026-06-04 23:09:14 -07:00
ywkang c699e2ddfc gqa(ddd): rewrite DDD-0060 to match current ADR (two-kernel composite hybrid)
Supersede the old greenlet-primitive/load_async/single-kernel DDD. Align to
ADR-0060's composite-hybrid + hierarchical CUBE-Group SP with two kernels:
decode+SP (head-replicated, contiguous C×P static shard, 2-level
reduce-to-root) and prefill+SP (1 Q head/CUBE, Ring KV, no reduce). Updated
file plan (lazy tl.load, scratch_scope, broadcast-opt; evolve
_attention_mesh_mlo_2d/_kv; DPPolicy.cube_start; llama70b_4sip.yaml),
placement (contiguous shared KV), phase plan (P1..P8), verification, perf
model, risks, glossary. Defers design rationale to ADR-0060 (now
authoritative); open items point to ADR-0060 §B. ADR-0064 cost model noted.
Docs only.

Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>
2026-06-04 23:08:02 -07:00
ywkang 973a452b77 gqa(adr): sync ADR-0060 KO mirror to current EN (two-kernel design)
Regenerate the KO mirror to match the current EN: two SP kernels
(decode=reduce / prefill=ring), TL;DR full code for the 3 decode variants
+ prefill, 'Q replicated / M-fold' and '1 Q head per CUBE' terminology,
contiguous shared KV layout, opt2 tl.wait, and all SB items. Docs only.

Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>
2026-06-04 23:02:49 -07:00
ywkang 8de13efb9d gqa(adr): opt2 ex_composite decode needs tl.wait() before the reduction
The ex_composite #2 updates acc=(m,l,O) asynchronously on the scheduler and
the kernel never reads its output, so no auto-wait fires; acc is only final
after the last #2 in the serial chain. Add tl.wait() (drain all composites)
before hierarchical_reduce_and_store reads acc. opt1/opt3 don't need it
(their composite outputs are consumed in-iteration -> auto-wait). Docs only.

Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>
2026-06-04 22:49:59 -07:00