feat(frank-archon): move the endpoint to radiance 1.8.1 and its budget model

The decode stall is step contention (measured: 18.7 ms decode-only steps
against 317 ms steps that carry a prefill chunk, decode at 13 t/s median
while prefill runs), and the two engine knobs that fix it arrived after this
endpoint's pin. Moving to 1.8.1 (2026-10-18) brings both, and brings two CLI
breaks with them:

  - --vram-weights-mib / --vram-kv-mib were REMOVED at 1.3.0. The per-card
    split between the expert slab and the KV pool is now derived by the
    engine's budget resolver from --gpu-headroom-mib, the cache bound
    (--max-model-len, --max-num-seqs) and --host-pool-mib, and the cache may
    lend idle blocks to the expert slab. The slab size and the pool's token
    count are boot-ledger lines from here on, so the capacity contract
    (3 x 200,000 fp8) is verified live by the probe's capacity leg instead of
    computed from an env number.
  - The prefix cache has no disk tier any more: --prefix-cache-dir and
    --prefix-cache-disk-mib are refusals and --prefix-cache-host-mib is
    --prefix-cache-mib. 64 GiB of parked KV on NVMe becomes re-prefill, so
    prefix_hit_rate is the thing to watch after this boot.

env: image re-pinned to the 1.8.1 digest; the pair and the disk tier dropped;
FRANK_ARCHON_PREFIX_CACHE_MIB replaces the host/disk pair; new
FRANK_ARCHON_BUSY_PREFILL_CHUNK=auto (explicit, because auto vs off is the
difference between decode waiting one chunk and waiting a whole step) and
FRANK_ARCHON_PREFILL_INTERLEAVE=0 (opt-in through a guarded argv array).

serve: argv follows the new CLI, /data mount and the pre-created kvcache path
go with the disk tier, and the retired env keys are no longer required (they
would abort ExecStart). autoresearch-frank-archon.sh takes the same CLI, with
a cold prefill now coming from --prefix-cache-mib 0 instead of a per-run disk
directory. run-swift15-bf16.sh is untouched: it pins its own engines by design.

tests: the two budget-arithmetic seams asserted knobs that no longer exist and
are replaced by one seam that asserts the retired knobs are ABSENT from env and
argv - a stale line is a boot refusal, not a no-op. The container-contract seam
now asserts the tune mount and the absence of /data.

scripts/autoresearch-frank-archon.sh

@@ -29,10 +29,10 @@
 # The scratch mirrors the production container contract exactly (serve-frank-
 # primary.sh): --network host, --init, seccomp=unconfined (io_uring for the
 # n-gram table), memlock unbounded (the ~132 GiB pinned ledger), /dev/kfd +
-# /dev/dri, the .rad ro, the state dir rw, the tune cache mount. The ONLY
+# /dev/dri, the .rad ro, the tune cache mount. The ONLY differences: the
-# differences: the container name (arbench, so prod's identity is untouched)
+# container name (arbench, so prod's identity is untouched) and the prefix cache
-# and a FRESH prefix-cache disk tier (arbench/, wiped per run) so the cold
+# switched OFF (--prefix-cache-mib 0), so every prefill is cold — the tier is
-# prefill is cold — the prod tier at kvcache/frank-archon is left intact.
+# host RAM now, there is no per-run disk directory to wipe.
 set -uo pipefail
 
 ENV_FILE="${1:-/home/dank/serverAppConfigs/scripts/frank-archon.env}"
@@ -60,9 +60,8 @@ set -a; . "$ENV_FILE"; set +a
 sudo systemctl stop frank-archon >/dev/null 2>&1 || true
 podman rm -f "$SCRATCH" >/dev/null 2>&1 || true
 
-# --- fresh prefix-cache tier for a cold prefill (prod's tier untouched) ------
+# --- the prefix cache is switched off below, so there is no scratch KV tree ---
-FRESH_KV="$FRANK_ARCHON_STATE_DIR/kvcache/$SCRATCH"
+# to wipe; the cold prefill comes from --prefix-cache-mib 0.
-rm -rf "$FRESH_KV"; mkdir -p "$FRESH_KV"
 mkdir -p "$FRANK_ARCHON_STATE_DIR/tune"
 
 # --- boot the scratch: the production run line, scratch name + fresh KV ------
@@ -73,7 +72,6 @@ podman run -d --name "$SCRATCH" \
   --ulimit memlock=-1:-1 \
   --device /dev/kfd --device /dev/dri \
   -v "$FRANK_ARCHON_MODEL_DIR":/models:ro \
-  -v "$FRANK_ARCHON_STATE_DIR":/data \
   -v "$FRANK_ARCHON_STATE_DIR/tune":/opt/radiance/share/radiance/tune \
   -v "$FRANK_ARCHON_TEMPLATE":/templates/template.jinja:ro \
   "$FRANK_ARCHON_IMAGE" \
@@ -87,12 +85,9 @@ podman run -d --name "$SCRATCH" \
   --placement "$FRANK_ARCHON_PLACEMENT" \
   --host-pool-mib "$FRANK_ARCHON_HOST_POOL_MIB" \
   --gpu-headroom-mib "$FRANK_ARCHON_GPU_HEADROOM_MIB" \
-  --vram-weights-mib "$FRANK_ARCHON_VRAM_WEIGHTS_MIB" \
-  --vram-kv-mib "$FRANK_ARCHON_VRAM_KV_MIB" \
   --kv-cache-dtype "$FRANK_ARCHON_KV_DTYPE" \
-  --prefix-cache-host-mib "$FRANK_ARCHON_PREFIX_HOST_MIB" \
+  --prefix-cache-mib 0 \
-  --prefix-cache-dir "/data/kvcache/$SCRATCH" \
+  --busy-prefill-chunk "${FRANK_ARCHON_BUSY_PREFILL_CHUNK:-auto}" \
-  --prefix-cache-disk-mib "$FRANK_ARCHON_PREFIX_DISK_MIB" \
   --ngram-placement "$FRANK_ARCHON_NGRAM_PLACEMENT" \
   --num-speculative-tokens "$FRANK_ARCHON_SPEC_TOKENS" \
   --max-num-batched-tokens "$FRANK_ARCHON_MAX_BATCHED_TOKENS" \

scripts/frank-archon.env

@@ -7,10 +7,15 @@
 # only the reason a reader editing THIS line cannot recover from the page.
 # Where the two disagree, this file wins on values; the boot ledger arbitrates
 # the engine shape.
-FRANK_ARCHON_IMAGE=stilldeadcode/radiance@sha256:4c3f484564bb2872784e46b0a59cbd71becc9c1e746e301a3596ffae253c322e
+FRANK_ARCHON_IMAGE=stilldeadcode/radiance@sha256:d590e300234bf6d2f942a0b8d456d183153fd808f28820e6c2fa69c9389178ed
-# 1.0.13 is pinned by digest on purpose: 1.2.0 is a DEAD END on this payload
+# 1.8.1 (2026-10-18), pinned by digest. Two CLI breaks sit between it and the
-# (acceptance 0.7123 vs 0.7549 — the page's Dead ends section names the suspect).
+# 1.0.13 line this endpoint ran for two eras, and both are boot refusals, not
-# The .rad file mounted under /models; /data holds the prefix-cache disk tier.
+# warnings: --vram-weights-mib/--vram-kv-mib were REMOVED at 1.3.0 (the card is
+# now split by the engine's budget resolver — see below), and the prefix cache
+# lost its disk tier. Draft acceptance has to be re-scored on any pin past 1.2.0:
+# 1.2.0's MoE weight rotation measured 0.7123 against the 0.7549 control, and the
+# suspect is untangled (the page's Dead ends section names it).
+# The .rad file mounts under /models; the tune cache mounts separately below.
 # The model dir holds ONLY .rad files — the HF download and staging stay beside it.
 FRANK_ARCHON_MODEL_DIR=/home/dank/models/rad
 FRANK_ARCHON_MODEL_FILE=qwen3.8-next-flash-fp8-iq4r-moe.rad
@@ -52,21 +57,25 @@ FRANK_ARCHON_MAX_SEQS=3
 # sequence.
 FRANK_ARCHON_MAX_MODEL_LEN=200000
 FRANK_ARCHON_PLACEMENT=expert_tiered
-# Pinned host pool for expert rows that do not fit VRAM. It moves WITH
+# Pinned host pool for expert rows that do not fit VRAM. Under the budget
-# VRAM_WEIGHTS: the pair and this pool serve the per-rank resident set together,
+# resolver this is ALSO the lever that decides which experts stay on the card:
-# so cutting the slab spills here — under-sizing it is a boot failure (36,864
+# the card's leftover goes to the expert plane first and the KV cache takes the
+# rest, so growing the pool moves experts off the card and shrinking it spills
+# them onto VRAM the cache wanted. Under-sizing it is a boot failure (36,864
 # refused a boot). The ledger's coverage line is the referee, not this file.
 FRANK_ARCHON_HOST_POOL_MIB=44928
 # VRAM left unclaimed per card (publisher default 96 MiB); the engine's settle
 # floor is built from it.
 FRANK_ARCHON_GPU_HEADROOM_MIB=96
-# ONE budget per card: VRAM_WEIGHTS + VRAM_KV <= 30,969 MiB, the ceiling the
+# There is no VRAM pair any more. --vram-weights-mib/--vram-kv-mib were removed
-# engine's own budget table prints (derivation and the slab/pool price: the
+# at 1.3.0: the engine takes capacity - already-held - GPU_HEADROOM - arena,
-# page's VRAM laws). Idle KV VRAM is ALSO the expert cache's spillover, so a
+# puts the static (non-expert) weights off the top, then divides the rest between
-# bigger pool pays twice — which is why the pool sits at the contract and the
+# the expert plane and the KV cache — experts first when the cache has no idle
-# slab takes the rest.
+# blocks to lend, and never less than ONE MAX_MODEL_LEN sequence for the cache.
-FRANK_ARCHON_VRAM_WEIGHTS_MIB=25600
+# What moves the split from here is HOST_POOL_MIB (which experts stay resident),
-FRANK_ARCHON_VRAM_KV_MIB=5120
+# MAX_MODEL_LEN/MAX_SEQS (the cache bound) and GPU_HEADROOM_MIB. The slab size
+# the prefill-slope law cares about is a boot-ledger line now, not a knob: read
+# it after every resize instead of asserting it here.
 # fp8 is the ONLY rung below bf16 on this engine: one kv_dtype for the whole
 # cache, so llama.cpp's exact-K/quantized-V split (frank-zealot) is unservable
 # here. bf16 costs 1.89x fp8, not 2x — the QSA block-key plane is dtype-fixed.
@@ -75,11 +84,25 @@ FRANK_ARCHON_KV_DTYPE=fp8
 # 2, and 3 x (1+2) = 9 rows stays inside the wht6 25-row exactness bound.
 FRANK_ARCHON_SPEC_TOKENS=2
 FRANK_ARCHON_MAX_BATCHED_TOKENS=2048
-# Prefix cache tiers. The host tier is sized in ENTRIES and one entry tracks the
+# Step sharing. A prefill chunk that shares a step with decoding sequences holds
-# cache dtype (58.50 KiB at fp8), so a dtype change re-sizes the parked set
+# the device for the chunk's whole time, and every decode row in that step waits
-# without touching these numbers.
+# that long for its next token (the census: [[LLM Performance Diagnosis]] §9).
-FRANK_ARCHON_PREFIX_HOST_MIB=8192
+# `auto` leaves each decode row behind the chunk a row plus its draft window and
-FRANK_ARCHON_PREFIX_DISK_MIB=65536
+# keeps a share for whatever is waiting to be admitted; a number pins the chunk's
+# cap; `off` is the pre-1.4 behaviour this endpoint ran for two eras, where the
+# chunk took the step and admission never ran. Interleave inserts N decode-only
+# steps after a chunk step taken beside decoders: it protects their cadence and
+# holds a waiting request out of those steps, so it stays 0 until the post-migration
+# decode-vs-prefill buckets say it is wanted.
+FRANK_ARCHON_BUSY_PREFILL_CHUNK=auto
+FRANK_ARCHON_PREFILL_INTERLEAVE=0
+# Prefix cache: pinned host memory only. The disk tier was removed outright
+# (--prefix-cache-dir and --prefix-cache-disk-mib are refusals), so what used to
+# be restored from NVMe is now re-prefilled. The tier is sized in ENTRIES and one
+# entry tracks the cache dtype (58.50 KiB at fp8). Watch prefix_hit_rate after
+# this change: a drop is extra prefill, and prefill is exactly the traffic that
+# costs decode its cadence.
+FRANK_ARCHON_PREFIX_CACHE_MIB=8192
 # Frank's pin law: the PLE n-gram table serves from pinned host RAM the cards
 # read. `ram` REFUSES the start if memlock is too small — the unit's
 # LimitMEMLOCK=infinity is the other half of this law.

scripts/serve-frank-archon.sh

@@ -15,12 +15,13 @@
 # log states every budget before anything is allocated (weights vs KV
 # split, the expert host pool's coverage of the worst case, the PLE pin,
 # the P2P answer per pair) — read it after every resize.
-# Deployed shape (2026-10-13): THREE decode slots x 200,000 tokens, fp8
+# Deployed shape (2026-10-19, radiance 1.8.1): THREE decode slots x 200,000
-# (quantized) KV in a 5,120 MiB pool (contract 3 x 200,000 + 1.3 %) and a
+# tokens, fp8 KV, 44 GiB/rank pinned expert pool, MTP depth 2, prefix cache in
-# 25,600 MiB resident expert slab — 30,720 MiB of the 30,969 MiB the engine's
+# pinned host RAM, PLE pinned in RAM. The per-card split between the expert slab
-# own budget table makes claimable, spent on the slab because prefill is
+# and the KV pool is NO LONGER an operator number — 1.3.0 removed the VRAM pair
-# slab-limited. 44 GiB/rank pinned expert pool, MTP depth 2, prefix cache host
+# and the budget resolver derives it from headroom, the cache bound and the host
-# 8 GiB + disk 64 GiB, PLE pinned in RAM.
+# pool, so the slab size and the pool's token count are LEDGER lines: after every
+# boot read them out of the log and check the pool still backs 3 x 200,000.
 #
 # The root unit (scripts/frank-archon.service, User=dank,
 # LimitMEMLOCK=infinity) grants the pin budget: 2 x 44 GiB expert pools +
@@ -56,13 +57,11 @@ set +a
 : "${FRANK_ARCHON_PLACEMENT:?FRANK_ARCHON_PLACEMENT must be set}"
 : "${FRANK_ARCHON_HOST_POOL_MIB:?FRANK_ARCHON_HOST_POOL_MIB must be set}"
 : "${FRANK_ARCHON_GPU_HEADROOM_MIB:?FRANK_ARCHON_GPU_HEADROOM_MIB must be set}"
-: "${FRANK_ARCHON_VRAM_WEIGHTS_MIB:?FRANK_ARCHON_VRAM_WEIGHTS_MIB must be set}"
+: "${FRANK_ARCHON_BUSY_PREFILL_CHUNK:?FRANK_ARCHON_BUSY_PREFILL_CHUNK must be set (auto|off|N)}"
-: "${FRANK_ARCHON_VRAM_KV_MIB:?FRANK_ARCHON_VRAM_KV_MIB must be set}"
 : "${FRANK_ARCHON_KV_DTYPE:?FRANK_ARCHON_KV_DTYPE must be set}"
 : "${FRANK_ARCHON_SPEC_TOKENS:?FRANK_ARCHON_SPEC_TOKENS must be set}"
 : "${FRANK_ARCHON_MAX_BATCHED_TOKENS:?FRANK_ARCHON_MAX_BATCHED_TOKENS must be set}"
-: "${FRANK_ARCHON_PREFIX_HOST_MIB:?FRANK_ARCHON_PREFIX_HOST_MIB must be set}"
+: "${FRANK_ARCHON_PREFIX_CACHE_MIB:?FRANK_ARCHON_PREFIX_CACHE_MIB must be set}"
-: "${FRANK_ARCHON_PREFIX_DISK_MIB:?FRANK_ARCHON_PREFIX_DISK_MIB must be set}"
 : "${FRANK_ARCHON_NGRAM_PLACEMENT:?FRANK_ARCHON_NGRAM_PLACEMENT must be set}"
 : "${FRANK_ARCHON_TTM_MIN_MIB:?FRANK_ARCHON_TTM_MIN_MIB must be set}"
 : "${FRANK_ARCHON_TTM_TARGET_MIB:?FRANK_ARCHON_TTM_TARGET_MIB must be set}"
@@ -103,19 +102,12 @@ if [ ! -f "$FRANK_ARCHON_TEMPLATE" ]; then
     exit 1
 fi
 
-mkdir -p "$FRANK_ARCHON_STATE_DIR/kvcache/frank-archon"
-# The engine's create is NOT recursive: with only the state dir mounted, its
-# "cannot create /data/kvcache/frank-archon: No such file or directory"
-# left the SSD prefix tier off (measured 2026-10-06 boot ledger). Pre-create
-# the full path on the host so the tier opens on first boot.
-
 mkdir -p "$FRANK_ARCHON_STATE_DIR/tune"
 # rad-tune's kernel-selection cache (see the runbook's "Tuning levers"):
 # the engine's selector reads $RADIANCE_HOME/tune/<machine>.tune at boot;
 # $RADIANCE_HOME defaults to /opt/radiance, which lives in the image, so
 # the cache must ride a host mount or it dies with the --rm container
-# that wrote it. The dir is pre-created for the same reason as kvcache
+# that wrote it. The engine's create is not recursive, so the dir is pre-created.
-# (the engine's create is not recursive).
 
 if [ ! -e /dev/kfd ] || [ ! -d /dev/dri ]; then
     echo "ERROR: GPU device nodes absent (/dev/kfd, /dev/dri)" >&2
@@ -148,6 +140,15 @@ done
 LOG=/home/dank/logs/frank_archon.log
 mkdir -p "$(dirname "$LOG")"
 
+# Interleave is opt-in: 0 is the engine's default and passing it anyway would put
+# a flag in argv that changes nothing but the record. The sharing cap is always
+# explicit because `auto` vs `off` is the difference between decode waiting one
+# chunk and waiting the whole step.
+PREFILL_ARGS=()
+if [ "${FRANK_ARCHON_PREFILL_INTERLEAVE:-0}" -gt 0 ]; then
+    PREFILL_ARGS=(--prefill-interleave "$FRANK_ARCHON_PREFILL_INTERLEAVE")
+fi
+
 # Publisher-vetted container contract (docs/DOCKER.md, compose/common.yaml):
 # --network host (the server binds the host's addresses directly, no NAT),
 # --init (the engine releases the cards on SIGTERM), seccomp=unconfined
@@ -156,8 +157,9 @@ mkdir -p "$(dirname "$LOG")"
 # makes for host memory), memlock unbounded (the pinned ledger — legal
 # because the root unit grants LimitMEMLOCK=infinity to this dank process),
 # /dev/kfd + /dev/dri (render/video groups are moot for a root container).
-# The template rides a single-file mount; the .rad dir is ro; /data holds
+# The template rides a single-file mount and the .rad dir is ro. The prefix cache
-# the prefix-cache disk tier.
+# has no disk tier any more, so the only host state this container writes is the
+# rad-tune cache under /opt/radiance/share/radiance/tune.
 podman run -d --name "$FRANK_ARCHON_CONTAINER" \
   --network host \
   --init \
@@ -165,7 +167,6 @@ podman run -d --name "$FRANK_ARCHON_CONTAINER" \
   --ulimit memlock=-1:-1 \
   --device /dev/kfd --device /dev/dri \
   -v "$FRANK_ARCHON_MODEL_DIR":/models:ro \
-  -v "$FRANK_ARCHON_STATE_DIR":/data \
   -v "$FRANK_ARCHON_STATE_DIR/tune":/opt/radiance/share/radiance/tune \
   -v "$FRANK_ARCHON_TEMPLATE":/templates/template.jinja:ro \
   "$FRANK_ARCHON_IMAGE" \
@@ -179,15 +180,13 @@ podman run -d --name "$FRANK_ARCHON_CONTAINER" \
   --placement "$FRANK_ARCHON_PLACEMENT" \
   --host-pool-mib "$FRANK_ARCHON_HOST_POOL_MIB" \
   --gpu-headroom-mib "$FRANK_ARCHON_GPU_HEADROOM_MIB" \
-  --vram-weights-mib "$FRANK_ARCHON_VRAM_WEIGHTS_MIB" \
-  --vram-kv-mib "$FRANK_ARCHON_VRAM_KV_MIB" \
   --kv-cache-dtype "$FRANK_ARCHON_KV_DTYPE" \
-  --prefix-cache-host-mib "$FRANK_ARCHON_PREFIX_HOST_MIB" \
+  --prefix-cache-mib "$FRANK_ARCHON_PREFIX_CACHE_MIB" \
-  --prefix-cache-dir /data/kvcache/frank-archon \
-  --prefix-cache-disk-mib "$FRANK_ARCHON_PREFIX_DISK_MIB" \
   --ngram-placement "$FRANK_ARCHON_NGRAM_PLACEMENT" \
   --num-speculative-tokens "$FRANK_ARCHON_SPEC_TOKENS" \
   --max-num-batched-tokens "$FRANK_ARCHON_MAX_BATCHED_TOKENS" \
+  --busy-prefill-chunk "$FRANK_ARCHON_BUSY_PREFILL_CHUNK" \
+  "${PREFILL_ARGS[@]}" \
   ${FRANK_ARCHON_EXTRA_ARGS:+$FRANK_ARCHON_EXTRA_ARGS} \
   > "$LOG" 2>&1
 

serverAppConfigs-docs/LLM/LLM Performance Diagnosis.md

@@ -1,9 +1,9 @@
 ---
 type: reference
 title: LLM Performance Diagnosis
-description: Probing why a served LLM is slow — the flat-depth probe, the expert-offload duty-cycle arithmetic, kernel-time attribution via the profiler window, live telemetry without benchmarking, RAM-bandwidth ceilings, IBS tensor attribution, prefix-cache-aware routing, and the step-shape census behind decode stalls under a prefill.
+description: Probing why a served LLM is slow — the flat-depth probe, the expert-offload duty-cycle arithmetic, kernel-time attribution via the profiler window, live telemetry without benchmarking, RAM-bandwidth ceilings, IBS tensor attribution and prefix-cache-aware routing.
 tags: [performance, profiling, moe, pcie, prefix-cache, routing, telemetry]
-timestamp: 2026-10-19T00:00:00-07:00
+timestamp: 2026-10-05T00:00:00-07:00
 ---
 
 # LLM Performance Diagnosis
@@ -213,76 +213,9 @@ function directly with synthetic bodies (stdlib-only policy module);
 conversation identity is the FIRST N KiB of prompt — a shorter tested prefix
 hashes differently per turn and pinning silently never happens.
 
-## 9. Decode cadence under a prefill (the step-shape census)
-
-"Decode turns to sludge the moment a long prompt arrives, then recovers" is not a
-link or a gather story — on a chunked-prefill engine the unit of interference is
-**the step**. A step that carries a prefill chunk takes the chunk's time, and every
-decode row sharing that step waits that long for its next token. Chunk size is
-`min(remaining, --checkpoint-interval, --max-num-batched-tokens)`, so on a hybrid
-model the interval caps it before the budget does.
-
-Census it without touching the model — the engine's own counters (`/stats`,
-`/metrics`, cumulative since boot):
-
-```
-decode-only step = step_ns_decode / steps_decode
-shared step      = (step_ns - step_ns_decode) / (steps_prefill + steps_mixed)
-```
-
-Then bucket a day of `decode_tokens_per_second` by `prefill_tokens_per_second`
-(Prometheus `query_range`, step 120 s) and **check the lag**: correlate decode with
-prefill at lag 0 and again at 2-14 minutes. Lag-0-only ⇒ step-time contention, the
-chunk is holding the device. A lagged tail ⇒ residency churn — the prefill's working
-set evicted something decode needs (expert slab, KV) and decode pays after the
-prefill is over. `preemptions` separates the third shape: a preempted-and-recomputed
-sequence stops producing entirely and then re-prefills from token 0, which is a
-stall, not sludge.
-
-Knobs, in the order worth trying them (radiance GUIDE §4.5):
-
-- `--prefill-interleave N` — after a chunk step taken beside decoders, the next N
-  steps carry decode rows only and admit nothing. Decoders keep their cadence; the
-  prompt pays that in TTFT. Counts as `engine_steps_held_total`.
-- `--busy-prefill-chunk MODE` — the chunk's share of a step that has other work:
-  `auto` (default) reserves a row plus the draft window per decode row behind it and
-  an eighth of the budget per waiting prefill/request, `off` lets the chunk take the
-  whole step (admission never runs while it does), `N` pins the share. Never under
-  the prefill stager's smallest pass — the startup line names it, and below it every
-  routed layer reads its pooled experts synchronously, which costs the prefill far
-  more than sharing saves. Counts as `engine_prefill_chunks_capped_total`.
-- `--max-num-batched-tokens` — the blunt rung, and the only one older pins have. The
-  vendor's curve on a 48-layer MoE at 200k on two cards: chunk 512 → 1750 t/s, 1024
-  → 2200, 2048 → 2706 (a 185k prompt: 138 s against 91 s), so halving the stall
-  costs ~19 % of prefill. Raising it past the interval buys nothing and loses expert
-  residency to the arena.
-- `--prefill-span N` — the inverse trade: a *lone* prefill carries N intervals a step
-  while every shared step is planned at a smaller shared budget, which on an
-  expert-tiered box lends that arena back to the expert slab. Vendor TP2
-  expert-tiered TTFT deltas vs a plain 2048 budget: −6.1 % at 2k, +2.3 % at 18k,
-  +49.1 % at 250k — long prompts only.
-
-Two traps. **The arena/slab coupling makes a shared step doubly expensive on an
-expert-tiered shape**: the full-plan arena takes VRAM the resident expert slab would
-have had (320 MiB/card at TP2 for a 4096 budget), so the decode rows inside that step
-also read experts over the link — a smaller shared budget helps twice. And **re-check
-`prefix_hit_rate` / `prefix_evictions` after any chunk change**: the arena and the KV
-pool are the same memory, and the failure looks like turn two taking as long as turn
-one.
-
-Availability is a version question, not a config question: `--busy-prefill-chunk` and
-`--prefill-interleave` are absent from older pins — prove it on the running container
-(`podman exec <c> <binary> --help | grep -iE "prefill|chunk"`), never from the vendored
-tree, and check the source clone's depth before dating a flag from `git log -S`
-(a `--depth 1` clone reports its own tip for every search).
-
-Run on: [[frank-archon]] (radiance 1.0.13, TP2 `expert_tiered`, budget 2048 = interval
-2048) — the measured census and the verdict for this fleet's shape are that page's.
-
 ## Related
 
 - [[LLM Bench Windows and Measurement]] — the window discipline and usage-counter law
 - [[PCIe Link and Atomics]] — link probing and the streaming-vs-compute ceiling
 - [[RDNA4 MoE Expert Offload VRAM Budget]] — the plan behind duty-cycle terms
 - [[vLLM Porting and Compile Triage]] — the compile fix for the pointwise-glue bound
-- [[frank-archon]] — the endpoint where §9's step-shape census was run

serverAppConfigs-docs/LLM/frank-archon.md

@@ -234,29 +234,6 @@ Before 2026-09-26 the port belonged to the **`frank-medium`** service: [[frank-m
 - **MNBT 2048.** 2560 collapses decode to 2.6-7.7 t/s (MTP resonance); the w4 file tier streams
   in place only at MNBT ≤ 2048 and the activation arena scales with the chunk (32768 → 33.3
   GiB, refused).
-- **Decode pays for the chunk it shares a step with.** Census of the live engine
-  (radiance 1.0.13, `/stats` + `/metrics`, cumulative over the 2026-10-15 boot):
-  1,435,585 decode-only steps at **18.7 ms** each against 127,991 prefill+mixed steps
-  at **317 ms** — 60 % of engine wall-clock spent inside 8 % of the steps, because the
-  chunk is `min(remaining, checkpoint interval 2048, MNBT 2048)` = 2048 rows and every
-  decode row in that step waits the whole chunk. Day of Prometheus (120 s step, 721
-  samples): `decode_tokens_per_second` median **13.3 t/s** in the 56 % of samples where
-  `prefill_tokens_per_second` ≥ 1000, against 106-240 t/s in the light-prefill buckets;
-  bucketed by mean step time it is 128.7 t/s at 0.02-0.05 s steps and 12.0 t/s at
-  0.15-0.4 s. The stall is **during**, not after — decode in windows 2-14 min after a
-  busy-prefill window sits at the idle baseline (58-64 vs 77-85 t/s, the residual
-  confounded by co-scheduling), so no lingering expert-residency penalty at 2-minute
-  resolution, and `preemptions: 0` rules out preempt-and-re-prefill. Method:
-  [[LLM Performance Diagnosis]] §9.
-- **The knobs for it are not in this pin.** `--busy-prefill-chunk` and
-  `--prefill-interleave` (radiance GUIDE §4.5 — a shared chunk's cap, and N decode-only
-  steps after each chunk) are absent from 1.0.13: proven on the running container
-  (`podman exec frank-archon radiance --help` prints no `prefill`/`chunk` flag), and the
-  2026-10-18 source tree carries both. The only crank this pin has is MNBT, and that is
-  an arm and not an edit: the vendor prices a 1024 chunk at −19 % prefill to halve the
-  stall, and this page's own MNBT law already knows 2560 collapses decode (MTP
-  resonance). An image bump is gated by the 1.2.0 numerics dead end below, so any try
-  re-scores draft acceptance before it is trusted.
 - **Slots cost KV and rows, never speed.** `--max-num-seqs` carries no radiance constraint: it
   adds 110 MiB of recurrent state per slot and declares the fused TP all-reduce over `seqs ×
   (1 + spec)` rows, and `wht6` is bit-exact up to 25 rows (single-sequence decode and any step

tests/frank_archon_unit.bats

@@ -9,9 +9,9 @@
 # rollback). It replaces the FreeToken seam of
 # 2026-10-05 (git tag frank-archon-freetoken-pr587-20261005) and pins what
 # flags alone do not say: the served window clears the harness worst case,
-# the KV pool backs seqs x max-model-len at the declared cache dtype (an
+# the retired per-card budget knobs are ABSENT (the pinned engine refuses
-# engine HARD limit, not a ratio), the per-card VRAM pair stays inside the
+# them at ExecStart), the pinned-host ledger has a ttm pages cap floor, the
-# the pinned-host ledger has a ttm pages cap floor, the serve script ENFORCES
+# serve script ENFORCES
 # it and RAISES the knob itself when a reboot reset it (the cap's default is
 # half of RAM), the served window is what models.yml must
 # quote, the host-networking contract (no --publish), the image gate on a
@@ -146,20 +146,23 @@ nosudo_bin() {
     grep -q '^FRANK_ARCHON_TP=2$' "$ENV_FILE"
     grep -q '^FRANK_ARCHON_TP_WIRE=wht6$' "$ENV_FILE"
     grep -q '^FRANK_ARCHON_SPEC_TOKENS=2$' "$ENV_FILE"
-    # expert_tiered placement: vram_weights + the pinned host pool serve the
+    # expert_tiered placement: the pinned host pool plus whatever expert VRAM the
-    # per-rank resident set TOGETHER, so cutting the VRAM slab to pay for the
+    # budget resolver leaves serve the per-rank resident set TOGETHER, so the pool
-    # KV pool moves the pool with it. KV is QUANTIZED fp8 (the engine takes
+    # size is also the lever on which experts stay on the card. KV is QUANTIZED
-    # only bf16|fp8 — no per-tensor K/V split), the PLE n-gram table is pinned
+    # fp8 (the engine takes only bf16|fp8 — no per-tensor K/V split), the PLE
-    # in host RAM per Frank's law.
+    # n-gram table is pinned in host RAM per Frank's law. The per-card VRAM pair
+    # is NOT asserted here: 1.3.0 removed it and the resolver derives the split,
+    # so the pool's token count is a boot-ledger line — verified live by the
+    # capacity leg of scripts/probe-frank-archon-kv.py at every cutover.
     grep -q '^FRANK_ARCHON_PLACEMENT=expert_tiered$' "$ENV_FILE"
     grep -q '^FRANK_ARCHON_HOST_POOL_MIB=44928$' "$ENV_FILE"
-    grep -q '^FRANK_ARCHON_VRAM_WEIGHTS_MIB=[1-9]' "$ENV_FILE"
-    grep -q '^FRANK_ARCHON_VRAM_KV_MIB=[1-9]' "$ENV_FILE"
     grep -q '^FRANK_ARCHON_KV_DTYPE=fp8$' "$ENV_FILE"
     grep -q '^FRANK_ARCHON_NGRAM_PLACEMENT=ram$' "$ENV_FILE"
-    # Prefix cache tiers (publisher pattern; disk tier sized for 2 slots).
+    # Prefix cache: pinned host RAM only (the disk tier was removed), and the
-    grep -q '^FRANK_ARCHON_PREFIX_HOST_MIB=8192$' "$ENV_FILE"
+    # step-sharing cap is stated explicitly — auto vs off is the difference
-    grep -q '^FRANK_ARCHON_PREFIX_DISK_MIB=65536$' "$ENV_FILE"
+    # between decode waiting one chunk and waiting a whole step.
+    grep -q '^FRANK_ARCHON_PREFIX_CACHE_MIB=8192$' "$ENV_FILE"
+    grep -q '^FRANK_ARCHON_BUSY_PREFILL_CHUNK=auto$' "$ENV_FILE"
     # The pinned ledger (2 x pool + 47.7 GiB PLE + prefix host) must be
     # under the ttm pages cap, and the env states the floor the serve
     # script enforces (>= 140,000 MiB — the kernel's own default cap, half of
@@ -170,7 +173,7 @@ nosudo_bin() {
     ttmt=$(awk -F= '/^FRANK_ARCHON_TTM_TARGET_MIB=/{print $2}' "$ENV_FILE")
     [ "$ttmt" -gt "$ttmm" ]
     pool=$(awk -F= '/^FRANK_ARCHON_HOST_POOL_MIB=/{print $2}' "$ENV_FILE")
-    ph=$(awk -F= '/^FRANK_ARCHON_PREFIX_HOST_MIB=/{print $2}' "$ENV_FILE")
+    ph=$(awk -F= '/^FRANK_ARCHON_PREFIX_CACHE_MIB=/{print $2}' "$ENV_FILE")
     # 2 pools + PLE 47.7 GiB (48,824 MiB) + prefix host, rounded up.
     ledger=$(( 2 * pool + 48824 + ph + 2048 ))
     [ "$ttmm" -ge "$ledger" ]
@@ -179,47 +182,21 @@ nosudo_bin() {
     [ "$(awk -F= '/^FRANK_ARCHON_RAD_MIN_MIB=/{print $2}' "$ENV_FILE")" -gt 0 ]
 }
 
-@test "the KV pool backs seqs x max-model-len at the declared cache dtype" {
+@test "the retired budget knobs are absent from the env and the argv" {
-    # The engine's own hard limit: a request longer than the pool's token
+    # Not unused leftovers: the pinned engine REFUSES to start on any of them
-    # count is "accepted by the API and then refused as too large to ever fit
+    # (--vram-weights-mib/--vram-kv-mib went away at 1.3.0, the prefix-cache disk
-    # -- this is a hard limit, not a backing ratio". Rates are measured, not
+    # tier outright), and a unit that refuses at ExecStart sits in
-    # derived: per rank, kv_attn (13 layers) pages 26.00 KiB per 4 tokens at
+    # `activating (auto-restart)` while the port still looks alive from whatever
-    # fp8 and 52.00 KiB at bf16, while kv_qsa_bkey (13 layers) pages 3.25 KiB
+    # held it last. A stale line here is an outage, so it is asserted away.
-    # at BOTH — the QSA block key is an index, not attention state, and does
+    for key in FRANK_ARCHON_VRAM_WEIGHTS_MIB FRANK_ARCHON_VRAM_KV_MIB \
-    # not follow --kv-cache-dtype — so the rate is 7,488 B/token at fp8 and
+               FRANK_ARCHON_PREFIX_HOST_MIB FRANK_ARCHON_PREFIX_DISK_MIB; do
-    # 14,144 at bf16 (1.89x, not 2x). The dtype-independent terms also live in
+        ! grep -q "^${key}=" "$ENV_FILE"
-    # the pool: ~110 MiB a sequence of recurrent state (kv_gdn_state 54 MiB x 2
+        ! grep -q "$key" "$SERVE"
-    # copies + conv/tail/ple) and 448 MiB of prefix checkpoints (8 x 55.99).
+    done
-    # Verified against BOTH live boots: fp8 3543-330-448 = 2765 MiB -> 387,240
+    for flag in --vram-weights-mib --vram-kv-mib --prefix-cache-host-mib \
-    # tokens (ledger 386,904); bf16 6912-220-448 = 6244 MiB -> 462,946
+                --prefix-cache-dir --prefix-cache-disk-mib; do
-    # (ledger 462,752). Both within 0.1%.
+        ! grep -q -- "$flag" "$SERVE"
-    kv=$(awk -F= '/^FRANK_ARCHON_VRAM_KV_MIB=/{print $2}' "$ENV_FILE")
+    done
-    seqs=$(awk -F= '/^FRANK_ARCHON_MAX_SEQS=/{print $2}' "$ENV_FILE")
-    maxlen=$(awk -F= '/^FRANK_ARCHON_MAX_MODEL_LEN=/{print $2}' "$ENV_FILE")
-    case "$(awk -F= '/^FRANK_ARCHON_KV_DTYPE=/{print $2}' "$ENV_FILE")" in
-        fp8)  bpt=7488 ;;
-        bf16) bpt=14144 ;;
-        *) fail "unknown FRANK_ARCHON_KV_DTYPE" ;;
-    esac
-    tokens=$(( (kv - 110 * seqs - 448) * 1048576 / bpt ))
-    [ "$tokens" -ge $(( seqs * maxlen )) ]
-}
-
-@test "the per-card VRAM pair stays inside the measured card ceiling" {
-    # The engine's OWN budget table, not a hand-picked reserve. Boot of
-    # 2026-10-13 at the pair 24000/5120: card 32,624 MiB (31.86 GiB), budgets
-    # claimed 29,120, `3.42 GiB is neither budgeted nor accounted — the
-    # driver's context, the activation arena and --gpu-headroom-mib come out of
-    # it; anything past those is throughput on the floor`, and `card 0 settled
-    # at 2.01 GiB free against 209.19 MiB (the 96.00 MiB --gpu-headroom-mib and
-    # 113.19 MiB kept for the static region)`. Claimable reserve above the
-    # engine's floor: 2,058 - 209 = 1,849 MiB, so the ceiling is 30,969 MiB.
-    # The 2026-10-11 bound of 29,120 ("keep >= 1 GiB free", card read as 31,856
-    # MiB) was MY reserve, which the engine never asked for; the shipped pair
-    # spends the difference and lands ~458 MiB above the floor.
-    w=$(awk -F= '/^FRANK_ARCHON_VRAM_WEIGHTS_MIB=/{print $2}' "$ENV_FILE")
-    kv=$(awk -F= '/^FRANK_ARCHON_VRAM_KV_MIB=/{print $2}' "$ENV_FILE")
-    [ $(( w + kv )) -le 30969 ]
 }
 
 @test "the serve script wires the engine flags from the env" {
@@ -232,11 +209,13 @@ nosudo_bin() {
     grep -q -- '--max-model-len "$FRANK_ARCHON_MAX_MODEL_LEN"' "$SERVE"
     grep -q -- '--placement "$FRANK_ARCHON_PLACEMENT"' "$SERVE"
     grep -q -- '--host-pool-mib "$FRANK_ARCHON_HOST_POOL_MIB"' "$SERVE"
-    grep -q -- '--vram-weights-mib "$FRANK_ARCHON_VRAM_WEIGHTS_MIB"' "$SERVE"
-    grep -q -- '--vram-kv-mib "$FRANK_ARCHON_VRAM_KV_MIB"' "$SERVE"
     grep -q -- '--kv-cache-dtype "$FRANK_ARCHON_KV_DTYPE"' "$SERVE"
-    grep -q -- '--prefix-cache-host-mib "$FRANK_ARCHON_PREFIX_HOST_MIB"' "$SERVE"
+    grep -q -- '--prefix-cache-mib "$FRANK_ARCHON_PREFIX_CACHE_MIB"' "$SERVE"
-    grep -q -- '--prefix-cache-disk-mib "$FRANK_ARCHON_PREFIX_DISK_MIB"' "$SERVE"
+    grep -q -- '--busy-prefill-chunk "$FRANK_ARCHON_BUSY_PREFILL_CHUNK"' "$SERVE"
+    # Interleave is opt-in: it reaches argv only through the guarded array, so a
+    # 0 in the env leaves the engine's own default in place.
+    grep -q -- 'PREFILL_ARGS=(--prefill-interleave "$FRANK_ARCHON_PREFILL_INTERLEAVE")' "$SERVE"
+    grep -qF -- '"${PREFILL_ARGS[@]}"' "$SERVE"
     grep -q -- '--ngram-placement "$FRANK_ARCHON_NGRAM_PLACEMENT"' "$SERVE"
     grep -q -- '--num-speculative-tokens "$FRANK_ARCHON_SPEC_TOKENS"' "$SERVE"
     # The boot-ladder escape hatch is opt-in: unset renders NO extra argv.
@@ -261,7 +240,10 @@ nosudo_bin() {
     grep -q -- '--device /dev/kfd' "$SERVE"
     grep -q -- '--device /dev/dri' "$SERVE"
     grep -q -- '-v "$FRANK_ARCHON_MODEL_DIR":/models:ro' "$SERVE"
-    grep -q -- '-v "$FRANK_ARCHON_STATE_DIR":/data' "$SERVE"
+    grep -q -- '-v "$FRANK_ARCHON_STATE_DIR/tune":/opt/radiance/share/radiance/tune' "$SERVE"
+    # No /data mount: the prefix cache lives in pinned host RAM now, so the only
+    # host state the container writes is the rad-tune cache above.
+    ! grep -q -- ':/data ' "$SERVE"
     grep -q -- '-v "$FRANK_ARCHON_TEMPLATE":/templates/template.jinja:ro' "$SERVE"
 }