1. `madvise(MADV_DONTNEED)` on the `181 MB` of source BF16 dense matrices in `mtp-q2_0.gguf` after quantizing them into `mq8_` (`90 MB` `Q8_0`) + switching `draft_vocab` from `106,299` tokens (`145 MB`) to `draft_vocab_en.bin` (`40,525` tokens, `55 MB`) saves **`271 MB` of RAM**, allowing `STRATA_METAL_ARENA_GB=6.5` (`9.9 GB` resident RSS, `-1.0 GB` lower than baseline!).
2. Capping `mtp_encode`'s local QSA sliding window to `256` cells (`4` chunks of 64 instead of `33`) and running `mtp_prefill` only on the last `256` tokens of the final prompt chunk eliminates the multi-chunk `mtp_prefill` lag on `12K–32K` prompts (`314–330 tok/s` end-to-end 2K prefill!).
3. Setting `STRATA_METAL_PREFETCH_DRAFT=0` in `stream.cpp` (`ahead()` only prefetches for root token `t=0`) and `AcceptMoE` (`arXiv:2608.02989`) draft routing in `router.metal`/`moe.metal` (`sg > 0` protects `r_prot = 1` and squares `moce_scale`) cuts speculative SSD traffic from `332 -> 177 MB/window` (`94.1%` arena hit rate!) and pushes **32K-context decode to `30.37 tok/s` (`persona_chat`), `33.44 tok/s` (`reasoning`), `34.41 tok/s` (`coding`), and `42.48 tok/s` (`prompt_2048tok_ops`, `3.26 tok/round`, `89.8%` acceptance)**!
4. **Round 5 Prefill + Decode + Scratch Aliasing + Deterministic Lookahead (`gr_norm_h_moec`, `gr_apply_moec`, `gr_norm_h4`, `gr_norm` `rv[10]`, `gr_norm_comb_4s`, `qsa_prep#qf16`, `-580 MB` Scratch Aliasing, `stream.cpp` Lookahead Fix):** Folded `mm_combine` into `gr_norm_h_moec` and `gr_apply_moec` (eliminating `47/48` `mm_combine` dispatches and `2.01 GB` DRAM traffic/chunk), added per-token 4-stream `gr_norm_h4` (`-18.3%`), skipped dead `p.mixed` FP32 writes in `gemm_hc_up` (`-11.3%`), cached `gr_norm` in registers + added 4-stream `gr_norm_comb_4s`, fused FP16 query output into `qsa_prep#qf16` (`1.98x` faster, `-8.91 ms/chunk`), aliased disjoint GDN/QSA prompt scratch buffers (**cutting `MT=2048` transient prompt scratch from `2.16 GB -> 1.58 GB`, `-770 MB` vs original `2.35 GB`**), and fixed `stream.cpp` `at_layer` to deterministically reclaim unused prompt lookahead slots.
27 unmodified lines
32. **Round 33 `gdn_step_t` Critical-Path `kl` Split + Pre-Barrier-3 `state` Commit (`-1.1%..-4.1%` Across `32/32` GDN Configs) + `gr_norm` Apply-Hoist & Pre-Offset Pointers (`-6%..-11%`) + `GrdUnit<T_Q8_0, 2>` Packed `char4` Decode (`-10%..-16%`) (`audits/opus_r33_gr.md`, `audits/sol_r33_qsa.md`, `audits/argon_r33_gdn.md`):** Split `tot_q` / `rsq` / `ql` / `g` / `be` / `vj` across Barrier 2 in `gdn_step_t` (`gdn.metal`) so only `kl` sits on the critical path before the 32-step `kv` FMA loop, moved `hist_out` writeback before Barrier 1 (killing `hst` live ranges across all 4 barriers on `GDN_NTOK == 1`), and issued the 32 global `state` stores before Barrier 3 to overlap the 64 KB/head state writeback with `ib == 0`'s readout reduction (`0.9589x..0.9895x` on `plane = 0`, `0.9717x..0.9959x` across all `16/16` production `plane = 49152` configs, `88/88` bitwise `PASS`) + pre-offset `moe_combine_sh` & `swiglu_prep` (`glue.metal`, `24/24` bitwise `PASS`); hoisted `if (a.apply)` and pre-offset pointers in `gr_norm` (`gr.metal`, **`-6%..-11%` at `ntok=1..4`**, `-2%..-3%` at `ntok=7..8`) and added `GrdUnit<T_Q8_0, 2>` keeping `Q8_0` codes packed in `char4 q[2][8]` (`8` VGPRs/row vs `32` floats) for `_r2` `gr_down` (**`-13%..-16%` at `ntok=7`, `-10%..-15%` at `ntok=8`**, `100%` bitwise `PASS`), cutting pure GPU `kprof` at `T=1983` to **`3,153.46 ms` (`628.51 tok/s` pure GPU prefill, `3,270.77 ms` serialized sum!)** and slashing `mtp_ms` to new all-time records across `reasoning` (**`323.71 ms`, `-12.4%` vs `369.70 ms`**), `persona_chat` (**`383.38 ms`, `-9.8%` vs `424.85 ms`**), and `prompt_2048tok_ops` (**`193.49 ms`**).
33. **Round 34 `gemm_hc_down` `TN = 96` Tail-Tile Decomposition (`-5.05%..-7.18%`) + `grd_acc` `ROLL = true` at `KS = 4` (`-1.9%..-4.6%` on `_r2`) + `W8<T_IQ3_S>::block` & Coalesced `half4` `HS` Store + `T_IQ2_XS` `sboff` (`audits/opus_r34_gr.md`, `audits/sol_r34_prompt.md`, `audits/argon_r34_moemm.md`):** Replaced `gemm_hc_down<TM, 128, SG>`'s 128-column tail tile (`tg.x = 2`, `c0 = 256`, where only `68` columns `256..323` exist) with a single `96`-column (`3 x 32`) `hc_down_tile<TM, 96, SG>`, cutting `gemm_hc_down` on the quiet GPU by **`-5.05%` at `T=512` (`ratio 0.9495`), `-6.60%` at `T=1024` (`ratio 0.9340`), `-7.18%` at `T=1983` (`1.1762 -> 1.0927 ms`, `ratio 0.9282`), and `-7.03%` at `T=2048` (`1.2062 -> 1.1209 ms`, `ratio 0.9297`, making `gemm_hc_down` faster than `gemm_hc_up` in full-model `kprof` for the first time ever: `125.998 ms` vs `132.822 ms`!)**; added `ROLL = F == T_Q8_0 && NR == 2 && KS == 4` to `grd_acc` (`gr.metal`) so packed `Q8_0` `NR=2` (`GrdUnit<T_Q8_0, 2>`) keeps its token loop rolled at `ntok = 4..6` (`-4.6 / -3.1 / -1.9%` faster `4_4_r2` at `ntok = 4/5/6`, `-13.7%` and `-23.9%` faster than `4_4` at `ntok = 5, 6`) while keeping `window.cpp:1165` at `ntok > 4` to preserve 324-threadgroup cold-DRAM latency hiding at `ntok = 4`; and added `W8<T_IQ3_S>::block` + `F == T_IQ3_S` `half4` `HS` epilogue stores (`+0.48%` at `T=2048`) + `T_IQ2_XS` `sboff` reuse (`-0.69%` at `T=1024`, `-1.25%` at `T=2048`) in `moe_mm.metal`, pushing `prompt_2048tok_ops` to **`432.78 tok/s` (`4,584.29 ms` end-to-end prefill) and `42.27 tok/s` (`3,004.68 ms` decode)** and `@10.2K` decode to **`25.04 tok/s` (`39.93 ms/tok`, `1,237.88 ms`)**!
34. **Round 35 `Wr`/`Wr2` Router Dequant Reuse (`-47` Dispatches/Chunk) + `gemm_f16_16_96_2` `Walbe` + `M % 128 <= 64` `64_128_4` (`1.14x` @ `M = 306`) + `hc_up_tile` Row-Tail Trim (`-2.5%` @ `T = 289`) + `mtp_rms_xprep` / `mtp_embed` / `mtp_slop_pen` Vectorization (`audits/opus_r35_dense.md`, `audits/sol_r35_prompt.md`, `audits/argon_r35_mtp.md`):** Ping-ponged `p.Wr` and `p.Wr2` by layer parity (`l & 1`) in `Window::prompt_chunk` (`window.cpp`), eliminating **`47` redundant `dq_f16_0` router dequantizations per chunk (`2,094 -> 2,047` dispatches in `kprof`)**, added `gemm_f16_16_96_2` (`TN = 96`) for `Walbe` at `M >= 640` (**`1.16x` / `-13.6%` faster at `M = 1983`**), selected `64_128_4` instead of `128_64_4` on big-N GEMMs when `M < 1536 && M % 128 in 1..64` (**`1.14x` / `-23.5 ms` faster chunk total at `M = 306`**), added `hc_up_tile<16/32, TN, SG, REG>` row-tail trimming to `gemm_hc_up` (**`-2.5%` at `T = 289`**), and vectorized/unrolled `mtp_rms_xprep` (**`-37.5%` at `n=2560`, `-35.8%` at `n=10240`**), `mtp_embed` (**`-15.8%..-31.6%` across all 13 GGUF formats**), `mtp_slop_pen` (**`-96.5%` on `mode=0`, `-45.7%..-70.6%` on `mode=1`, `-31.0%..-63.9%` on `mode=2`**), and `router_route` (**`-0.2%..-2.1%`**) (`100%` bitwise `PASS` across all suites!).
35. **Round 36 Decode `predL_` / `predL2_` Token-0 Fast Path When `STRATA_METAL_PREFETCH_DRAFT <= 0` (`-16.0%` Hot / `-6.8%` Cold Across `93` Router GEMVs/Window) + Guarded `TM > 32` Row-Tail Trimming in `gemm_hc_down` & `gemm_swiglu_up` (`audits/opus_r36_decode.md`, `audits/sol_r36_prompt.md`, `audits/argon_r36_qsa.md`):** Added `tile_ntok` to `Window::gemv` (`window.cpp`) so when `STRATA_METAL_PREFETCH_DRAFT <= 0` (`= 0` in production, where `ExpertStream::ahead` only reads `t = 0`), the `93` router-guess GEMVs (`47` `predL_` + `46` `predL2_`, `Q8_0` `2560 -> 512`) run at `ntok = 1` on the window's tile (`gemv_8_16_1_4_1#1`), producing **100% bit-for-bit-identical `t = 0` predictions** while cutting their GPU time by **`-16.0%` hot (`21.78 -> 18.30 us`) and `-6.8%` cold (`23.91 -> 22.29 us`)**; added `if constexpr (TM > 32)` row-tail (`TM = 16 / 32`) trimming to `gemm_hc_down` (**`-4.71%` at `T=1025`, `-3.73%` at `T=1041`**) and `gemm_swiglu_up` (**`-1.42%` at `T=1025`, `-1.14%` at `T=1041`, `-0.78%` at `T=1987`**) while preserving `TM = 32` (`SG = 2`) kernels byte-for-byte (`252/252` `epi` bitwise checks `PASS`); and confirmed `qsa_prep` / `qsa_score_mm` are at their M5 register/barrier optimum.
36. **Round 37 Multi-Chunk Prompt Hot-Expert LRU & Scratch Pool Preservation (`stream.h`, `stream.cpp`, `window.cpp`):** Passed `multi_chunk = (n > C)` into `prompt_region(true, n > C)` -> `hold_region(true, multi_chunk)` so 1-chunk prompts (`<= 2,048` tokens) run 100% identically (`42.49 tok/s` / `2,989.17 ms` `@2K` decode — new all-time record, `88.9%` accept), while multi-chunk prompts (`> 2,048` tokens, e.g., `prompt_albedo_11k.txt` at `10,180` tokens) keep `!x.hot` scratch slots at `lru_back(s)` across chunks, mark `pass == 1` demotions `x.hot = false` in `victim()` so `pass == 0` reuses them instead of evicting more `hot` decode experts, and restrict `allow_hot` lookahead to `distance == 1` — boosting `@10.2K` decode from `25.26 tok/s` (`1,227.18 ms`, `45.2%` accept, `2,713` SSD reads) to **`34.01–34.74 tok/s` (`892.47–911.51 ms`, `+34.6–37.5%` faster, `78.3%` accept, `2,073` SSD reads / `-23.6%` fewer SSD reads)** and `@10.2K` prefill from `423.48 tok/s` (`24,038.85 ms`) to **`458.34–472.89 tok/s` (`21,527–22,210 ms`, `-1.83s to -2.51s` faster)**, with pure GPU `T=1983` prefill (`kprof`) hitting **`3,131.29 ms` (`633.28 tok/s` — new all-time record)**.