All four columns come from one interleaved session on 27 September: upstream, fork, upstream, fork… so every multiplier is against the same control measured minutes apart. Control is the pinned upstream ds4 binary bd66c402, the base this fork is built on, compiled with the same toolchain; every arm produced the same output SHA-256, so the comparison is like-for-like. The one-drive column needs no replicas at all — same laptop, same single internal SSD, same model file; it is the portable part of this result and it is software only. The enclosure columns add weighted split reads across byte-identical copies of the 518 GB file (prefill 10:5 and 10:5:5, decode 10:6 and 10:6:6). Fork arms run profile v41-stack-20260927 with 4,600 cached experts; upstream sizes its cache automatically (3,688). Steady excludes the first decode step; generation includes it; both exclude startup and prefill; The earlier rungs (15 to 19 September: 14.38 one drive, 18.45 three drives against a 10.6 control) and the 512/512 stack qualifications (20.30 → 22.74 against our own 21 September engine on 27 September; 22.92 → 23.26 on 28 September with a post-MoE flush and an eviction pre-scan) remain on the research pages.
4 October, prefill. The 30 September read-ahead staging plus a continuous prefill reader, Engram row-table reads on upstream’s prefetch thread from the first layer, and a conditional read-ahead prior (how often an expert at one layer followed each expert of the previous layer in 19 other prompts, applied to this prompt’s own routing). Qualified against the 30 September binary at +6.4% (512/512) and +6.5% (512/200), both sides at a 3,600-expert cache, output byte-identical on every arm. The three-drive prefill is drive-bound (the lanes read 177 GB per 512-token prompt at the 25.5 GB/s three-drive ceiling), so only read-ahead precision moves it. Qualification package · Ladder package · Release
30 September, prefill. Read-ahead staging fetches the next layer’s likeliest experts while the GPU computes the current one, ranked by a hotlist built from other prompts, and the routed MoE runs in two waves around the remaining reads. Qualified against the 28 September binary in the same session: 45.55 → 68.59 prompt tokens/s at 512/512 (+50.6%) and 45.50 → 68.09 at 512/200 (+49.6%), decode unchanged, output identical on every arm. The ladder above used a 3,600-expert cache and the qualification 4,200, because the 4,600 champion cache tripped the swap-growth guard on a machine that had not been rebooted; decode rungs are therefore below the 27 September table, which remains the decode reference. Qualification package · Ladder package.
