Every fv-ml1 link on the Homepage dashboard was broken. Measured against the
live dashboard API before the fix: 16 entries pointing at the dead 10.250.50.54
and zero at the live 10.251.50.54, covering gen, M.O.G.-SEC, Scriberr, Embed,
Rerank, Reward, Coder, Dockge and six dormant seats.
The miss was structural, not careless. fv-ml1-rename-sweep.sh works from an
allowlist assembled from files that mention the HOST, and a homepage.href label
mentions only an IP -- so every stack whose sole stale reference was a label
fell outside it. The allowlist now covers those 24 files, and records how to
derive the list next time (grep the old address, subtract history) rather than
enumerating from memory.
History is still untouched, and the exclusions are now written down with the
reason each one keeps the old address: recorded benchmark results, whose
base_url is part of a measurement's provenance; the one LiteLLM comment
preserving a retired hand-test endpoint; and the cutover runbooks, where the old
address is the subject matter.
Two bugs found while applying it, both fixed here:
- deploy-stack.sh rejected any stack name containing a dot, so qwen3.5-122b,
qwopus3.5-122b and mistral-medium-3.5 could not be deployed by the script at
all. The check exists to stop path traversal, which means rejecting ".." and
"/" -- not every dot. Traversal is now rejected explicitly and tested.
- stacks/scriberr/.env.example allowed CORS only from the dead IP and from
scriberr.ana.internal, which no longer resolves; the box is at the fv site
and DNS already carries scriberr.fv.internal. The live .env had both stale
origins, i.e. an allowlist with nothing reachable in it.
Host side, applied separately: canonical pushed for the 16 stacks whose only
difference from the host was this renumber, and an in-place address-only fix for
the nine whose host copy has genuinely drifted or has no canonical copy, so that
drift survives for a deliberate reconciliation instead of being clobbered. Every
compose.yaml on fv-ml1 now reads 10.251.50.54. The labels themselves only take
effect at container creation, so the running containers still need recreating.
Root cause of the multi-day degeneration hunt, operator-confirmed: the AEON
NVFP4 W4A4 quant (sakamakismile/Qwen3.8-27B-AEON-ULTIMATE-UNCENSORED-NVFP4,
full W4A4 incl. attention) went degenerate ~15-20% of generations in real
multi-turn use and forced regenerates. MTP, prefix-caching, and the gateway
all merely AMPLIFIED it, which is why MTP-off, APC-off, and the vLLM #51113
fix each 'helped' a synthetic probe without fixing it -- three plausible
false root-causes, each passing one clean run then failing in real use.
The fix was the WEIGHTS: the in-house JonathanColetti/Heretic mixed
NVFP4+FP8 build (qwen38-27b-uncensored-nvfp4-mixed, FP8 attention not W4A4,
same base, same MTP) is coherent through long multi-turn with MTP ON. W4A4
*attention* was the defect; FP8 attention is not.
This commit:
- GEN_MODEL -> the mixed FP8-attn build (primary gen until DavidAU 3.8 lands)
- GEN_IMAGE pinned to vllm/vllm-openai:nightly-311b3513... (v0.27.2rc1.dev150,
carries #51113; pinned by sha so it does not drift on the next pull)
- AEON weights PURGED from /tank (no-good), safety-checked not-in-use first
- playbook 3.8: the stochastic-W4A4-degeneration lesson + isolate-weights-early
+ do-not-declare-a-fix-from-one-probe (it validated three non-fixes)
AEON is re-pullable from HF if ever needed, but the operator ruled it no-good.
The MTP-on + prefix-caching-off mitigation (63a3cb2) passed synthetic
7-turn probes but the operator still saw severe degeneration in real use.
A passing synthetic probe is NOT sufficient evidence -- it under-covers
real workloads (content distribution, conversation depth). Reverted to the
verified known-good: MTP off, prefix caching on (the 7bd38b3 state), ~half
decode speed but coherent. Operator is driving it to re-confirm.
Lesson reinforced (the recurring one this session): do not trust a
synthetic reproduction to VALIDATE a fix for a bug that only manifests in
the operator's real usage -- it validated a non-fix twice tonight.
The qwen3_5_mtp corruption (playbook 3.7) is gated on MTP x prefix-caching
TOGETHER (vllm#43559 / #47194), per both cross-frontier peers. Disabling
prefix caching (--no-enable-prefix-caching; vLLM V1 defaults it ON, so the
explicit --no- form is required) forces the GDN cache into a mode where the
partial-accept align-path bug is inert, so MTP can stay on.
Verified on our stack (AEON W4A4): MTP on + prefix-caching off -> the 7-turn
varied series stays coherent through 3.9k tokens, zero cross-turn bleed, at
104.6 tok/s / 53.6% acceptance -- the FULL MTP speedup restored (vs ~half
with MTP off), losing only prefix-cache reuse. All 7 aliases route.
Ruled out on the way: num_speculative_tokens=1 (corruption is
depth-independent, n=1 and n=2 both corrupt); switching to SGLang (vLLM /
SGLang / llama.cpp mainline all share the architectural GDN-rollback bug).
Proper upstream fix (#51113) is in main / v0.27.2rc0 only, not stable, so we
hold at APC-off rather than jump the fleet gateway to an RC.
Supersedes the MTP-off config from 7bd38b3.
Root cause of the long-hunted 'gen goes degenerate in conversation',
isolated 2026-08-16 and operator-confirmed. qwen3_5_mtp speculative
decoding corrupts Qwen3.8-27B output once cumulative multi-turn context
passes ~2,000 tokens: the draft head's bad tokens get accepted and the
reply degenerates into CONTEXT-BLEEDING (a 'describe durian' answer that
contained the Krebs-cycle and winter replies from earlier turns), then
collapses to a few words.
Isolation, each step measured on the varied 7-turn probe:
- not the gateway (identical input -> gateway == direct; echo intact)
- not presence_penalty (1.5/0.5/0.0 all collapse), not temperature
(1.0 collapses harder), not repetition (varied unrelated topics
collapse identically -> it is context length, not template-lock)
- model-INDEPENDENT across all three Qwen3.8-27B quants we serve
(AEON W4A4, unsloth FP8-attn, in-house mixed)
- Qwen3.6 (char-rp-reasoning) and Gemma-4 (char-rp) are CLEAN
- DECISIVE: same Qwen3.8 model + same conversation, MTP OFF -> coherent
through 4k+ tokens, no bleed. MTP is the cause.
Qwen3.6 runs the same qwen3_5_mtp method and is clean, so the 3.6 MTP
head/graft is fine and the 3.8 one is not (suspects: the bf16 MTP graft,
or spec depth 3). COST: ~half decode tok/s without spec decoding.
Accepted as known-good until the 3.8 MTP is fixed; first thing to try on
re-enable is num_speculative_tokens=1. Seat restored to AEON W4A4 (the
production choice); verified clean on the varied series after this change.
Measured on the restored model: at the template default xhigh, reasoning
runs 4,529-5,532 chars on a 3-turn history and was observed spiking to
9,261; medium holds it to 2,602-3,283 with content length unchanged or
better. Per-request overridable; an invalid value 400s.
SCOPE CAVEAT, stated because I applied this while chasing the wrong path:
this is a NO-OP for the alias, which sends enable_thinking:false and
produces zero reasoning. It affects only. The operator's
reported multi-turn failure was on , so this does not address it.
Operator reports AEON-ULTIMATE degenerate on long MULTI-TURN conversations.
Restored the previous model and removed the reasoning_effort default in
the same change, so the model is the only variable differing from the
pre-trial state and the operator's comparison is clean.
My acceptance gate did not cover this failure mode and should have. Every
probe was SINGLE-TURN -- quickbench, concbench, surface_test, the
long-form smokes -- so a defect that only appears as conversation history
accumulates was structurally invisible to all of it. The gate measures
decode speed, MTP acceptance, abliteration survival, and a 36k needle, and
passes a model that degrades across turns.
Verified restored via docker inspect rather than the compose file:
/model -> qwen38-27b-uncensored-nvfp4-mixed, --default-chat-template-kwargs
absent, MTP drafter loaded, all 7 aliases answering.
AEON weights retained at /tank/aimodels/qwen38-27b-aeon-ultimate-nvfp4 for
diagnosis; bench artifacts stay in services/gen-seat-mixed-quant/bench/.
Its single-turn numbers were real (104.22 tok/s, 52.3% MTP, 4/4
abliteration, 6/6 surface) -- they were just measuring the wrong thing.
Operator call: the incumbent abliterated model was the first one we could
find, not an optimised pick. sakamakismile/Qwen3.8-27B-AEON-ULTIMATE-
UNCENSORED-NVFP4 (base AEON-7 BF16, abliterix-abliterated, Apache-2.0),
byte-verified at /tank/aimodels/qwen38-27b-aeon-ultimate-nvfp4.
Measured on the same harness, same GPU, cache-busted per playbook 5.
Baseline was RE-measured live before the swap rather than trusted:
incumbent (W4A4+FP8 mixed) AEON (W4A4)
decode bs=1 94.09 tok/s 104.22 +10.8%
MTP acceptance 47.7% 52.3% +4.6pp
abliteration 4/4 4/4
surface 6/6 6/6
weights 22.5 GB 20.6 GB -8.4%
AEON concurrency: conc=1 98.48 tok/s aggregate; conc=6 381.29 aggregate /
63.55 per-stream, MTP holding 50.6% under load.
Surface 6/6 includes vision (image-judge rides this seat) and a 36k-token
needle retrieval, which was the specific risk in going full-W4A4 -- the
packager only validated 32k, and W4A4 long-context collapse is in our own
notes from the Granite work. It held.
reasoning_effort: the AEON template defaults to xhigh (template line 47),
and at xhigh this model can spend its entire budget inside <think> and
emit no answer -- a silent-empty-response hazard for the automated
summarizer/classifier consumers. Seat now pins the default to medium via
--default-chat-template-kwargs, per-request overridable. Override PROVEN
live: chat_template_kwargs.reasoning_effort=bogus returns HTTP 400
carrying the template's own exception text, so caller values genuinely
reach the template and invalid ones fail loudly rather than silently
falling back. Empty GEN_REASONING_EFFORT omits the flag for models that do
not read the kwarg -- the Qwen3.6 line ignores it entirely, where setting
it would be a false lever.
All 7 aliases verified routing. Rollback is one .env line; the previous
build is untouched at /tank/aimodels/qwen38-27b-uncensored-nvfp4-mixed.
TWO GAPS, declared:
- Incumbent concurrency was never captured before the swap (I baselined
bs=1 only), so the conc=1/6 figures have no same-hardware comparator.
- Perplexity NOT measured. eval_quality correctly refused it: under
--speculative-config prompt_logprobs come back ~uniform (median rank
~130k), playbook trap 2. A real PPL number needs both seats served
without spec-decode.
Adds concbench.py (concurrent throughput; wall-clock aggregate, not
sum-of-rates, and delta-based MTP accounting).
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