frank-primary: four full windows + Restart=always (runtime survivability)

Five 262144-token contexts passed every boot gate (KV 1,350,182 / 5.15x) but
left 0 bytes free at runtime: a real client request (995-token prompt,
max_tokens=261149, sampling params straight from models.yml) killed Worker_TP1
with torch.OutOfMemoryError 'Tried to allocate 50.00 MiB ... 0 bytes free'.
Boot is not proof of runtime survivability.

Four slots x 262144 fp8 (KV_BYTES 8,311,013,376/rank) returns ~1.93 GiB per
rank for activations/graph capture.

Unit: Restart=always instead of on-failure — a runtime worker fault makes
vLLM's API server exit clean, so ExecStart returned 0 and on-failure never
fired, leaving the endpoint down until a human noticed. Also
StartLimitIntervalSec=0 and OOMScoreAdjust=-500.

scripts/frank-primary.env

@@ -60,18 +60,19 @@ FRANK_PRIMARY_PUBLISH=7770:7770
 FRANK_PRIMARY_LEGACY_CONTAINERS="frank-primary-r9v qwen-fp8"
 
 # --- qualified engine shape (2026-10-01 night ladder, Frank's method) ---------
-# SEQS 5 x MAXLEN 262144 at fp8 KV is the DEPLOYED shape (Frank's call: five
-# contexts of the model's FULL native window beats six shortened ones).
-# Measured: "GPU KV cache size: 1,350,182 tokens, Maximum concurrency for
-# 262,144 tokens per request: 5.15x" — 39,462 tokens of margin over the
-# 1,310,720-token contract.
-# The night's ladder, both contracts: at SEQS=3 bf16, 262144/245760 OOMed at
-# graph capture and 241664 was max possible (KV 732,359 / 3.03x). At SEQS=6
-# fp8, 6 x 241664 OOMed (tried 10.70 GiB with 9.18 GiB free) — six
-# full-length contexts do NOT fit on this box; five do.
+# SEQS 4 x MAXLEN 262144 at fp8 KV is the DEPLOYED shape: four contexts of
+# the model's FULL native window, with VRAM headroom the five-slot shape did
+# not have. Measured 2026-10-01: 5 x 262144 booted (KV 1,350,182 tokens /
+# 5.15x) but left ~0 bytes free at runtime, and a real client request
+# (995-token prompt, max_tokens=261149) killed the worker with
+# `torch.OutOfMemoryError: Tried to allocate 50.00 MiB ... 0 bytes free`.
+# Dropping to four slots returns ~1.93 GiB per rank for activations/graphs.
+# At SEQS=3 bf16, 262144/245760 also OOMed at boot and 241664 was max
+# possible; at SEQS=6 fp8, six full-length contexts do NOT fit at all
+# (6 x 241664 asked 10.70 GiB against 9.18 GiB free).
 FRANK_PRIMARY_MAXLEN=262144
-FRANK_PRIMARY_SEQS=5
-FRANK_PRIMARY_KV_BYTES=10388766720
+FRANK_PRIMARY_SEQS=4
+FRANK_PRIMARY_KV_BYTES=8311013376
 FRANK_PRIMARY_KV_DTYPE=fp8
 FRANK_PRIMARY_MNBT=1024
 FRANK_PRIMARY_GATHER_CHUNKS=32