fix(prompt-cache): template-aware assistant-primer splice — Qwen3.8 prefix cache hits again

[Kaden-Schutt]

Summary

Every conversational turn after the first re-prefilled the whole conversation on Qwen3.8 (measured lcp=26 against prior_len=118, 2–6.5 s of re-prefill per turn on the coding session) because the jinja prompt-cache replay prepends the live turn's generation primer to every cached assistant body on the assumption the template renders history turns bare. Qwen3.5's template does; Qwen3.8's template re-emits <think>\n\n</think>\n\n on history assistant turns when thinking is off, so the spliced render carried the empty-think block twice, diverged 4 tokens into the first answer, and the LCP never hit.

Token-level proof (HIPFIRE_QWEN_CACHE_TRACE=1, qwen3.8:27b.mq4, two-turn probe):

common[20..26]  "assistant\n<think>\n\n</think>\n\n"
prior_past[26]  "```python\ndef is_prime(n):…"
rend_past[26]   "<think>\n\n</think>\n\n```python…"   ← primer doubled
lcp=26 prior_len=118 rendered_len=148

The fix probes the template once (template_emits_history_primer: render a one-exchange history with a sentinel answer, check whether the primer sits between the assistant opener and the sentinel) and both lookups (AR in ar.rs, DFlash in qwen.rs) prepend the primer only when the template does not re-emit it. Qwen3.5 behaviour is unchanged; Qwen3.8 gets the extension it was getting only in error paths.

Which crate(s) does this touch?

• crates/hipfire-runtime (prompt_frame.rs: probe + test), crates/hipfire-generate (ar.rs, qwen.rs: two lookup sites)

Evidence (RX 7900 XTX, 4bc750e73, qwen3.8:27b.mq4/.mq5, greedy, thinking off)

Two-turn probe: lcp=26 → lcp=118 = prior_len, cached_tokens=118, and the fixed render is shorter (144 vs 148 — the double primer is gone).

Full 8-turn coding session (session_coding.json, serve_harness, q8 KV), before → after (AR arm shown; the fixed build's two arms are byte-identical turn by turn):

turn	ctx	cached before	prefill before	cached after	prefill after
t2	3564	0	4654 ms	3514	208 ms
t3	5885	0	4529 ms	5843	189 ms
t4	8603	0	6411 ms	8563	213 ms
t8	15490	0	2083 ms	15456	258 ms

22–30× cheaper per-turn prefill; all 8 turns pass with recall 3/3, same gen counts as before (greedy ⇒ output-preserving).

Not caused by this bug, measured in the same sessions: mq5 + draft on a 24 GB card OOMs at ~5k ctx regardless (#686 dropped the pairing on those tiers and has the details).

Test plan

• cargo test -p hipfire-runtime --lib prompt_frame — 53 pass incl. new history_primer_probe_distinguishes_qwen35_and_qwen38_templates (bare template → prepend, re-emitting template → don't, empty primer → don't)
• cargo test -p hipfire-generate — 221 pass
• Hardware: probe + full session above, both AR and DFlash arms

[hipfire-sol]

hw-gate sol prelim

summary: This head is a large stacked change, not only the advertised prompt-cache fix: it makes assistant-primer replay template-aware, adds registry-managed DFlash sidecars and prompt-file benchmark evidence, introduces source-aware pre-teardown admission and EP mesh labeling, changes DFlash allocation/rollback/context-exhaustion behavior, adds sticky GPU-fault handling, changes LFM batching eligibility and Llama MQ-V2 prefill admission, and updates MQ4-V2 documentation/tests. The two kernel files contain comment-only changes, but runtime dispatch and load/serve state machines materially change.

run_hardware: true
run_hardware_reasons: The Rust, HIP, registry, and documentation changes are ordinary hipfire product work with no obfuscated payloads or unexplained unsafe code.; The new filesystem reads are user-requested model and --prompt-file paths or registry-declared sidecars under the model directory; they do not read credentials or unrelated host state.; scripts/registry_gen.py only extends existing Hugging Face registry generation to annotate DFlash sidecars; it is not invoked by the runtime hardware routes.; Cargo.toml adds the ordinary md5 crate solely to stamp exact benchmark prompt bytes.; Real hardware is required because the change reaches gfx12 MQ-V2 dispatch eligibility, model-source admission, DFlash GPU allocation/rollback, multi-turn recurrent prompt-cache state, and serve terminal behavior.

routes:

mode	tag	source	why
battery	qwen3.6:27b	bucket	bucket kernel,load,serve
chain	qwen3.6:27b	bucket	bucket kernel,load,serve
battery-dflash	qwen3.6:27b	bucket	bucket kernel,load,serve
chain-dflash	qwen3.6:27b	bucket	bucket kernel,load,serve
battery	ornith-1.5:35b-a3b-mq4r	bucket	bucket kernel,load,serve
chain	ornith-1.5:35b-a3b-mq4r	bucket	bucket kernel,load,serve
battery-dflash	ornith-1.5:35b-a3b-mq4r	bucket	bucket kernel,load,serve
chain-dflash	ornith-1.5:35b-a3b-mq4r	bucket	bucket kernel,load,serve
battery	lfm2.5:1.2b	bucket	bucket kernel,load,serve
chain	lfm2.5:1.2b	bucket	bucket kernel,load,serve
battery-dflash	lfm2.5:1.2b	bucket	bucket kernel,load,serve
chain-dflash	lfm2.5:1.2b	bucket	bucket kernel,load,serve
battery	qwen3.8:27b-mq4-xt	bucket	bucket kernel,load,serve
chain	qwen3.8:27b-mq4-xt	bucket	bucket kernel,load,serve
battery-dflash	qwen3.8:27b-mq4-xt	bucket	bucket kernel,load,serve
chain-dflash	qwen3.8:27b-mq4-xt	bucket	bucket kernel,load,serve

unavailable_routes:

(none)

claim_assessment: The author claims Qwen3.8 thinking-off history templates already emit the empty-think primer, so suppressing a second primer restores full multi-turn LCP/cache hits without changing generated bytes, while Qwen3.5-style behavior remains unchanged. Proof requires a real multi-turn Qwen3.8 chain showing coherent byte-stable outputs and cached-prefix growth after turn one, plus a Qwen3.5/3.6-family control showing no cache regression. The supplied PR-body timings and test counts are claims, not gate evidence.

questions_for_author:

• Why does PR fix(prompt-cache): template-aware assistant-primer splice — Qwen3.8 prefix cache hits again #692 contain thousands of lines of unrelated loader, registry, kernel-admission, DFlash transaction, EP topology, benchmark, and policy changes rather than only the prompt-cache fix?
• Was this head intentionally stacked on the fixes represented by PRs feat(dflash): registry-declared draft sidecars — pull fetches, auto uses, on requires #686/fix(admission): refuse unservable model/topology combinations before allocation (#683 family) #687/fix(bench): --prompt-file, prompt evidence in JSON, short-prompt prefill warning #689/fix(mq4v2): one MQ-V2 prefill admit rule for llama and qwen35; discriminating GEMM parity; spec §9 #690/fix(dflash): transactional draft ctors, emitter-error rollback, one ctx-cap predicate #691, and should the hardware verdict evaluate the complete stack as presented?

[hipfire-sol]

hw-gate evidence — 2 lane(s) — verdict fail

lane hiptrx (unknown)

hw-gate evidence

field	value
base	3bd2914bac09bb6d48b03cf5b0155473ff1bc922
head	fa30b3ae247a64f9acc44ddeeca28678c0ba9bf0
buckets	kernel,load,serve
host gfx	unknown
host rocm	7.15.26333-0000000
device	1
runner	hiptrx
daemon_md5	2f6b10605a61dcb45c86d8769ef3e06c
hipfire_md5	594eedc165bc975b7bc6d99a0217c258
build_seconds	337.46435594558716
verdict	fail
logs_dir	hw-gate-logs

fixtures

qwen3.6:27b

source: bucket sha256_ok: ✅ size_ok: ✅ status: fail reason: battery: harness exit 1; chain: harness exit 1; battery-dflash: harness exit 1; chain-dflash: harness exit 1

battery — exit 1 seconds 199.3 status fail

reason: harness exit 1

mode	idx	genre	finish	ctx	cached	gen	ans_words	prefill_tok_s	decode_tok_s	attractor	empty	runaway	recall_ok
battery	0		stop	34	0	186	90	3.1	18.2	False	False	False	True
battery	1		stop	30	0	86	78	502.2	36.0	False	False	False	True
battery	2		stop	31	0	19	16	520.7	36.2	False	False	False	True
battery	3		stop	47	0	31	8	561.8	36.1	False	False	False	True
battery	4		stop	47	0	6	2	564.2	36.2	False	False	False	True

qwen3.6:27b battery turn 0

```python
def longest_substring_without_repeating_chars(s: str) -> str:
    """
    Returns the longest substring of a string without repeating characters.
    
    Args:
        s: Input string
        
    Returns:
        The longest substring without repeating characters
    """
    if not s:
        return ""
    
    char_index = {}
    start = 0
    max_length = 0
    max_start = 0
    
    for end, char in enumerate(s):
        if char in char_index and char_index[char] >= start:
            start = char_index[char] + 1
        
        char_index[char] = end
        
        if end - start + 1 > max_length:
            max_length = end - start + 1
            max_start = start
    
    return s[max_start:max_start + max_length]
```

qwen3.6:27b battery turn 1

The sky appears blue during the day because sunlight interacts with Earth's atmosphere, scattering shorter blue wavelengths more widely than longer red wavelengths. At sunset, sunlight travels through a much thicker layer of atmosphere to reach the observer, which filters out most of the blue light and allows the longer red and orange wavelengths to dominate. This shift in scattered light composition is why the sky transitions from blue to red as the sun dips below the horizon.

qwen3.6:27b battery turn 2

The capital of France is Paris, and the river that runs through it is the Seine.

qwen3.6:27b battery turn 3

{
  "name": "Alice",
  "age": 34,
  "city": "Lisbon"
}

qwen3.6:27b battery turn 4

Answer: 43

chain — exit 1 seconds 198.9 status fail

reason: harness exit 1

mode	idx	genre	finish	ctx	cached	gen	ans_words	prefill_tok_s	decode_tok_s	attractor	empty	runaway	recall_ok
chain	0		stop	44	0	124	54	512.3	35.8	False	False	False	True
chain	1		stop	224	169	204	109	413.5	35.7	False	False	False	True
chain	2		stop	454	429	76	62	299.5	35.7	False	False	False	True
chain	3		stop	564	531	87	71	305.5	35.6	False	False	False	True
chain	4		stop	683	652	65	46	359.4	35.6	False	False	False	True

qwen3.6:27b chain turn 0

```python
def merge_sorted(a, b):
    """Merge two sorted lists into a single sorted list without using sorted()."""
    result = []
    i, j = 0, 0
    while i < len(a) and j < len(b):
        if a[i] <= b[j]:
            result.append(a[i])
            i += 1
        else:
            result.append(b[j])
            j += 1
    # Append remaining elements
    result.extend(a[i:])
    result.extend(b[j:])
    return result
```

qwen3.6:27b chain turn 1

To find the total distance traveled, we calculate the distance for each segment of the trip using the formula:

**Distance = Speed × Time**

### Step 1: Calculate the distance for the first segment
*   **Speed:** 60 mph
*   **Time:** 2.5 hours
*   **Distance:** $60 \times 2.5 = 150$ miles

### Step 2: Calculate the distance for the second segment
*   **Speed:** 40 mph
*   **Time:** 1.5 hours
*   **Distance:** $40 \times 1.5 = 60$ miles

### Step 3: Calculate the total distance
Add the distances from both segments together:
$$150 \text{ miles} + 60 \text{ miles} = 210 \text{ miles}$$

The train traveled a total of **210** miles.

qwen3.6:27b chain turn 2

The primary cause of the seasons is the tilt of Earth’s rotational axis, which is inclined approximately 23.5 degrees relative to its orbital plane around the Sun. As Earth revolves, this constant axial tilt causes different hemispheres to receive varying intensities and durations of direct sunlight throughout the year. The resulting change in solar heating creates the distinct seasonal patterns we experience.

qwen3.6:27b chain turn 3

For forty years, Elias had watched the waves beat against the jagged cliffs with predictable monotony. One gray morning, however, he noticed a glint of unnatural color tangled among the dark rocks near the waterline. As he carefully cleared away the seaweed, he uncovered a brass time capsule, perfectly preserved from a ship lost decades ago. The rusted seal on the lid promised secrets from a world he had long forgotten.

qwen3.6:27b chain turn 4

1. Write meaningful, descriptive variable and function names.
2. Keep functions small and focused on a single responsibility.
3. Write comprehensive tests to catch regressions early.
4. Document complex logic with clear comments and documentation.
5. Consistently adhere to a shared style guide and formatting rules.

battery-dflash — exit 1 seconds 198.6 status fail

reason: harness exit 1

no rows

chain-dflash — exit 1 seconds 198.7 status fail

reason: harness exit 1

no rows

ornith-1.5:35b-a3b-mq4r

source: bucket sha256_ok: ✅ size_ok: ✅ status: fail reason: battery: harness exit 1; chain: harness exit 1; battery-dflash: skipped (fixture ornith-1.5:35b-a3b-mq4r declares no dflash_draft); chain-dflash: skipped (fixture ornith-1.5:35b-a3b-mq4r declares no dflash_draft)

battery — exit 1 seconds 198.5 status fail

reason: harness exit 1

mode	idx	genre	finish	ctx	cached	gen	ans_words	prefill_tok_s	decode_tok_s	attractor	empty	runaway	recall_ok
battery	0		stop	34	0	127	62	23.3	15.0	False	False	False	True
battery	1		stop	30	0	108	98	462.5	58.3	False	False	False	True
battery	2		stop	31	0	16	13	478.7	64.1	False	False	False	True
battery	3		stop	47	0	22	6	686.1	67.6	False	False	False	True
battery	4		stop	47	0	17	7	687.6	46.2	False	False	False	True

ornith-1.5:35b-a3b-mq4r battery turn 0

```python
def longest_substring_without_repeating(s: str) -> str:
    start = 0
    max_start = 0
    max_length = 0
    seen = {}

    for end, char in enumerate(s):
        if char in seen and seen[char] >= start:
            start = seen[char] + 1
        seen[char] = end

        if end - start + 1 > max_length:
            max_length = end - start + 1
            max_start = start

    return s[max_start:max_start + max_length]
```

ornith-1.5:35b-a3b-mq4r battery turn 1

The sky appears blue during the day because sunlight interacts with the atmosphere through a process called Rayleigh scattering, in which shorter blue wavelengths of light scatter off gas molecules much more effectively than longer wavelengths, spreading blue light across the entire sky in every direction. At sunset, the Sun sits lower on the horizon, meaning its light must travel through a significantly thicker layer of atmosphere to reach your eyes. This longer path filters out most of the scattered blue light, allowing the longer red and orange wavelengths to dominate and paint the sky with warm hues.

ornith-1.5:35b-a3b-mq4r battery turn 2

The capital of France is Paris, and the Seine River runs through it.

ornith-1.5:35b-a3b-mq4r battery turn 3

{"name": "Alice", "age": 34, "city": "Lisbon"}

ornith-1.5:35b-a3b-mq4r battery turn 4

17 + 26 = 43

Answer: 43

chain — exit 1 seconds 198.8 status fail

reason: harness exit 1

mode	idx	genre	finish	ctx	cached	gen	ans_words	prefill_tok_s	decode_tok_s	attractor	empty	runaway	recall_ok
chain	0		length	44	0	256	153	719.7	71.0	False	False	True	True
chain	1		stop	353	0	144	75	178.5	61.7	False	False	False	True
chain	2		stop	523	497	90	74	443.8	53.1	False	False	False	True
chain	3		stop	647	613	132	107	549.5	44.5	False	False	False	True
chain	4		stop	811	779	84	62	461.6	49.2	False	False	False	True

ornith-1.5:35b-a3b-mq4r chain turn 0

```python
def merge_sorted(a, b):
    """Merge two sorted lists into a single sorted list.

    Uses a two-pointer approach that walks through both input lists in a
    single pass, always appending the smaller of the two current elements.
    Runs in O(n + m) time where n and m are the lengths of the inputs.
    """
    result = []
    i, j = 0, 0

    # Walk through both lists simultaneously.
    while i < len(a) and j < len(b):
        if a[i] <= b[j]:
            result.append(a[i])
            i += 1
        else:
            result.append(b[j])
            j += 1

    # Append whatever remains from either list.
    result.extend(a[i:])
    result.extend(b[j:])

    return result
```

**How it works:**

The function uses two pointers (`i` for `a`, `j` for `b`) that advance through the lists in parallel. At each step it compares the current elements and appends the smaller one, keeping the result sorted. Since the inputs are already sorted, you never need to look back — every comparison

ornith-1.5:35b-a3b-mq4r chain turn 1

# Total Distance Calculation

For each leg of the trip, I use the formula: **Distance = Speed × Time**

## Leg 1
- Speed: 60 mph
- Time: 2.5 hours
- Distance = 60 × 2.5 = **150 miles**

## Leg 2
- Speed: 40 mph
- Time: 1.5 hours
- Distance = 40 × 1.5 = **60 miles**

## Total
$$150 + 60 = \boxed{210 \text{ miles}}$$

The train traveled **210 miles** in total.

ornith-1.5:35b-a3b-mq4r chain turn 2

The seasons are caused by Earth's axial tilt of about 23.5 degrees relative to its orbit around the Sun. As Earth revolves around the Sun over the course of a year, different parts of the planet receive varying amounts of direct sunlight depending on their angle toward or away from it. This changing angle and duration of sunlight—not our distance from the Sun—is what produces the cyclical pattern of spring, summer, autumn, and winter.

ornith-1.5:35b-a3b-mq4r chain turn 3

Every dawn, Mara climbed the lighthouse tower to trace the sea's restless line with her gaze, never expecting anything but the usual drift of kelp and stone. That morning, however, a glint of glass caught the pale light near the jagged rocks, and she hurried down to investigate. Half-buried in the wet pebbles lay a sealed bottle, its letter inside so faded she could barely make out the words, yet they seemed written straight for her. She clutched it against her coat and looked out at the horizon, wondering if the ocean had finally carried her an answer to a question she had never dared to ask.

ornith-1.5:35b-a3b-mq4r chain turn 4

1. Name things clearly and consistently so their intent is obvious at a glance.
2. Keep functions small and focused on a single responsibility.
3. Avoid duplicating logic by extracting reusable helpers when patterns repeat.
4. Comment on "why," not "what," to explain reasoning behind non-obvious decisions.
5. Keep changes minimal and commit frequently so code stays easy to review and revert.

battery-dflash — exit 0 seconds 0.0 status skip

reason: fixture ornith-1.5:35b-a3b-mq4r declares no dflash_draft

no rows

chain-dflash — exit 0 seconds 0.0 status skip

reason: fixture ornith-1.5:35b-a3b-mq4r declares no dflash_draft

no rows

lfm2.5:1.2b

source: bucket sha256_ok: ✅ size_ok: ✅ status: fail reason: battery: harness exit 1; chain: harness exit 1; battery-dflash: skipped (fixture lfm2.5:1.2b declares no dflash_draft); chain-dflash: skipped (fixture lfm2.5:1.2b declares no dflash_draft)

battery — exit 1 seconds 198.5 status fail

reason: harness exit 1

mode	idx	genre	finish	ctx	cached	gen	ans_words	prefill_tok_s	decode_tok_s	attractor	empty	runaway	recall_ok
battery	0		stop	0	0	122	57	None	208.55	False	False	False	True
battery	1		stop	0	0	67	58	None	209.38	False	False	False	True
battery	2		stop	0	0	15	13	None	208.33	False	False	False	True
battery	3		stop	0	0	26	8	None	209.68	False	False	False	True
battery	4		stop	0	0	31	19	None	209.46	False	False	False	True

lfm2.5:1.2b battery turn 0

```python
def longest_unique_sub(s):
    char_index = {}
    start = 0
    max_length = 0
    max_sub = ""

    for i, char in enumerate(s):
        if char in char_index and char_index[char] > start:
            start = char_index[char] + 1
        char_index[char] = i
        if i - start + 1 > max_length:
            max_length = i - start + 1
            max_sub = s[start:i+1]

    return max_sub
```

lfm2.5:1.2b battery turn 1

The sky appears blue during the day because blue light from the sun is scattered more effectively by small atmospheric particles. At sunset, the sun is lower in the sky, so the red light travels through more atmosphere, dispersing and making the sky look red. This interplay of scattering and the sun's position creates the colors we see.

lfm2.5:1.2b battery turn 2

The capital of France is Paris, and the Seine River runs through it.

lfm2.5:1.2b battery turn 3

{
  "name": "Alice",
  "age": 34,
  "city": "Lisbon"
}

lfm2.5:1.2b battery turn 4

Let's add the numbers: 17 + 26.  
17 + 26 = 43  
So the final answer is: Answer: 43

chain — exit 1 seconds 198.3 status fail

reason: harness exit 1

mode	idx	genre	finish	ctx	cached	gen	ans_words	prefill_tok_s	decode_tok_s	attractor	empty	runaway	recall_ok
chain	0		stop	0	0	243	133	None	202.84	False	False	False	True
chain	1		stop	0	0	164	105	None	188.51	False	False	False	True
chain	2		stop	0	0	69	58	None	180.63	False	False	False	True
chain	3		stop	0	0	95	73	None	174.63	False	False	False	True
chain	4		stop	0	0	66	48	None	170.54	False	False	False	True

lfm2.5:1.2b chain turn 0

```python
def merge_sorted(a, b):
    """
    Merges two already-sorted lists into a single sorted list.

    Parameters:
    a (list): First sorted list
    b (list): Second sorted list

    Returns:
    list: A new sorted list containing all elements from both input lists.
    """
    i, j = 0, 0
    merged = []
    
    # Traverse both lists and merge them in sorted order
    while i < len(a) and j < len(b):
        if a[i] < b[j]:
            merged.append(a[i])
            i += 1
        else:
            merged.append(b[j])
            j += 1

    # Append remaining elements from list a, if any
    while i < len(a):
        merged.append(a[i])
        i += 1

    # Append remaining elements from list b, if any
    while j < len(b):
        merged.append(b[j])
        j += 1

    return merged
```

This function efficiently merges two sorted lists into a single sorted list using the `i` and `j` indexes.

lfm2.5:1.2b chain turn 1

Here's how to solve the problem step by step:

1. **First part of the journey:**
   - Speed = 60 mph
   - Time = 2.5 hours
   - Distance = Speed × Time = 60 × 2.5 = 150 miles

2. **Second part of the journey:**
   - Speed = 40 mph
   - Time = 1.5 hours
   - Distance = Speed × Time = 40 × 1.5 = 60 miles

3. **Total distance:**
   - Total Distance = Distance in first part + Distance in second part
   - Total Distance = 150 + 60 = 210 miles

**Final Answer:** 210 miles

The train traveled a total of **210 miles**.

lfm2.5:1.2b chain turn 2

The seasons on Earth are caused by the Earth's axial tilt of approximately 23.5 degrees relative to its orbit around the Sun. As the Earth revolves, different parts of the planet receive varying amounts of sunlight throughout the year, leading to seasonal changes. These shifts in sunlight intensity and angles create the cyclical patterns known as the seasons.

lfm2.5:1.2b chain turn 3

On a crisp winter morning, the lighthouse keeper noticed a small, weathered box washed up on the rocky shore, its contents mysterious. Curiosity piqued, he carefully opened the box to reveal an ancient map etched in faded ink. As he examined the map, it hinted at a long-lost treasure hidden near the coast. With a thrill of adventure, the keeper decided to follow the clues into the next phase of his daily duty.

lfm2.5:1.2b chain turn 4

1. Use clear and descriptive variable names to improve readability.  
2. Break your code into modular functions for better organization.  
3. Write comments to explain complex sections for future readers.  
4. Keep a consistent coding style to enhance maintainability.  
5. Regularly review and refactor code to eliminate redundancies.

battery-dflash — exit 0 seconds 0.0 status skip

reason: fixture lfm2.5:1.2b declares no dflash_draft

no rows

chain-dflash — exit 0 seconds 0.0 status skip

reason: fixture lfm2.5:1.2b declares no dflash_draft

no rows

qwen3.8:27b-mq4-xt

source: bucket sha256_ok: ✅ size_ok: ✅ status: fail reason: battery: harness exit 1; chain: harness exit 1; battery-dflash: harness exit 1; chain-dflash: harness exit 1

battery — exit 1 seconds 198.4 status fail

reason: harness exit 1

mode	idx	genre	finish	ctx	cached	gen	ans_words	prefill_tok_s	decode_tok_s	attractor	empty	runaway	recall_ok
battery	0		stop	34	0	129	58	64.3	43.9	False	False	False	True
battery	1		stop	30	0	100	88	359.4	49.5	False	False	False	True
battery	2		stop	31	0	16	13	378.6	62.5	False	False	False	True
battery	3		stop	47	0	31	8	454.8	58.2	False	False	False	True
battery	4		stop	47	0	9	3	455.1	31.7	False	False	False	True

qwen3.8:27b-mq4-xt battery turn 0

```python
def longest_substring_without_repeating(s: str) -> str:
    char_index = {}
    start = 0
    best_start = 0
    best_end = 0

    for end, char in enumerate(s):
        if char in char_index and char_index[char] >= start:
            start = char_index[char] + 1
        char_index[char] = end
        if end - start > best_end - best_start:
            best_start = start
            best_end = end

    return s[best_start:best_end + 1]
```

qwen3.8:27b-mq4-xt battery turn 1

During the day, sunlight scatters off the molecules in the atmosphere, with shorter blue wavelengths scattering more strongly in all directions, which makes the sky appear blue when viewed away from the sun. At sunset, the sun is lower on the horizon, so its light travels through a much thicker layer of the atmosphere, causing the blue light to scatter out of the direct line of sight. This leaves the longer red and orange wavelengths to dominate the view, resulting in the warm colors characteristic of a sunset.

qwen3.8:27b-mq4-xt battery turn 2

The capital of France is Paris, and the River Seine runs through it.

qwen3.8:27b-mq4-xt battery turn 3

{
  "name": "Alice",
  "age": 34,
  "city": "Lisbon"
}

qwen3.8:27b-mq4-xt battery turn 4

43

Answer: 43

chain — exit 1 seconds 198.7 status fail

reason: harness exit 1

mode	idx	genre	finish	ctx	cached	gen	ans_words	prefill_tok_s	decode_tok_s	attractor	empty	runaway	recall_ok
chain	0		stop	44	0	120	51	375.0	62.0	False	False	False	True
chain	1		stop	224	0	210	116	614.5	62.5	False	False	False	True
chain	2		stop	464	0	71	59	751.2	35.8	False	False	False	True
chain	3		stop	573	0	95	77	727.4	34.1	False	False	False	True
chain	4		stop	704	0	73	53	708.8	29.3	False	False	False	True

qwen3.8:27b-mq4-xt chain turn 0

```python
def merge_sorted(a, b):
    """Merge two sorted lists into a single sorted list."""
    result = []
    i, j = 0, 0
    while i < len(a) and j < len(b):
        if a[i] <= b[j]:
            result.append(a[i])
            i += 1
        else:
            result.append(b[j])
            j += 1
    # Append remaining elements
    result.extend(a[i:])
    result.extend(b[j:])
    return result
```

qwen3.8:27b-mq4-xt chain turn 1

To find the total distance traveled, we calculate the distance for each leg of the trip separately and then add them together. The formula for distance is:

$$ \text{Distance} = \text{Speed} \times \text{Time} $$

**Step 1: Calculate the distance for the first leg.**
*   Speed = 60 mph
*   Time = 2.5 hours
*   Distance = $60 \times 2.5 = 150$ miles

**Step 2: Calculate the distance for the second leg.**
*   Speed = 40 mph
*   Time = 1.5 hours
*   Distance = $40 \times 1.5 = 60$ miles

**Step 3: Add the distances together.**
*   Total Distance = $150 + 60 = 210$ miles

**Final Answer:**
The train traveled a total of **210** miles.

qwen3.8:27b-mq4-xt chain turn 2

The seasons are primarily caused by the tilt of Earth's axis relative to its orbital plane around the Sun. As Earth orbits, this tilt results in varying angles of sunlight and day lengths across different latitudes throughout the year. These changes determine the amount of solar energy received, leading to the cyclical pattern of winter, spring, summer, and fall.

qwen3.8:27b-mq4-xt chain turn 3

Elias brushed the brine from his coat and stepped onto the jagged rocks, expecting only seaweed or driftwood. Instead, his lantern light caught the glint of a brass pocket watch, perfectly intact and ticking softly in the foam. He pulled it from the cold water, recognizing the intricate engraving on the back as his late father's initials. For the first time in decades, the silence of the island felt less like solitude and more like a conversation.

qwen3.8:27b-mq4-xt chain turn 4

1. Write descriptive, single-purpose variable and function names.
2. Keep functions small and focused on one specific task.
3. Avoid code duplication by reusing logic through functions or modules.
4. Add concise comments explaining why code exists, not just what it does.
5. Write unit tests to verify behavior and enable safe refactoring.

battery-dflash — exit 1 seconds 198.4 status fail

reason: harness exit 1

no rows

chain-dflash — exit 1 seconds 198.6 status fail

reason: harness exit 1

no rows

kernel

status: fail
reason: harness exit 1

report pass: True

lane hipx (gfx1100)

hw-gate evidence

field	value
base	3bd2914bac09bb6d48b03cf5b0155473ff1bc922
head	fa30b3ae247a64f9acc44ddeeca28678c0ba9bf0
buckets	kernel,load,serve
host gfx	gfx1100
host rocm	7.15.26333-0000000
device	0
runner	hipx
daemon_md5	2f6b10605a61dcb45c86d8769ef3e06c
hipfire_md5	594eedc165bc975b7bc6d99a0217c258
build_seconds	47.34608697891235
verdict	fail
logs_dir	hw-gate-logs

fixtures

qwen3.6:27b

source: bucket sha256_ok: ✅ size_ok: ✅ status: fail reason: battery-dflash: harness exit 1; chain-dflash: harness exit 1

battery — exit 0 seconds 30.1 status pass

mode	idx	genre	finish	ctx	cached	gen	ans_words	prefill_tok_s	decode_tok_s	attractor	empty	runaway	recall_ok
battery	0		stop	34	0	132	62	3.3	17.6	False	False	False	True
battery	1		stop	30	0	76	65	439.9	49.8	False	False	False	True
battery	2		stop	31	0	19	16	451.0	49.9	False	False	False	True
battery	3		stop	47	0	31	8	462.2	49.8	False	False	False	True
battery	4		stop	47	0	6	2	466.0	50.0	False	False	False	True

qwen3.6:27b battery turn 0

```python
def longest_substring_without_repeating(s: str) -> str:
    char_index = {}
    start = 0
    max_length = 0
    max_start = 0
    
    for i, char in enumerate(s):
        if char in char_index and char_index[char] >= start:
            start = char_index[char] + 1
        char_index[char] = i
        if i - start + 1 > max_length:
            max_length = i - start + 1
            max_start = start
            
    return s[max_start:max_start + max_length]
```

qwen3.6:27b battery turn 1

During the day, the atmosphere scatters shorter blue wavelengths of sunlight in all directions, making the sky appear blue to our eyes. At sunset, sunlight travels through a thicker layer of atmosphere, which scatters away most of the blue and green light before it reaches the observer. This leaves the longer red and orange wavelengths to dominate the view, creating the characteristic colors of sunset.

qwen3.6:27b battery turn 2

The capital of France is Paris, and the river that runs through it is the Seine.

qwen3.6:27b battery turn 3

{
  "name": "Alice",
  "age": 34,
  "city": "Lisbon"
}

qwen3.6:27b battery turn 4

Answer: 43

chain — exit 0 seconds 23.9 status pass

mode	idx	genre	finish	ctx	cached	gen	ans_words	prefill_tok_s	decode_tok_s	attractor	empty	runaway	recall_ok
chain	0		stop	44	0	115	46	390.7	49.6	False	False	False	True
chain	1		length	215	160	256	125	392.8	49.7	False	False	True	True
chain	2		stop	493	44	85	72	285.8	49.6	False	False	False	True
chain	3		stop	612	579	107	80	294.6	49.6	False	False	False	True
chain	4		stop	751	720	70	50	351.0	49.5	False	False	False	True

qwen3.6:27b chain turn 0

```python
def merge_sorted(a, b):
    """Merge two already-sorted lists into one sorted list."""
    result = []
    i, j = 0, 0
    while i < len(a) and j < len(b):
        if a[i] <= b[j]:
            result.append(a[i])
            i += 1
        else:
            result.append(b[j])
            j += 1
    result.extend(a[i:])
    result.extend(b[j:])
    return result
```

qwen3.6:27b chain turn 1

To find the total distance traveled, we calculate the distance for each segment of the trip and then add them together.

**Step 1: Calculate the distance for the first segment.**
The train travels at 60 mph for 2.5 hours.
$$ \text{Distance}_1 = \text{Speed} \times \text{Time} $$
$$ \text{Distance}_1 = 60 \text{ mph} \times 2.5 \text{ hours} = 150 \text{ miles} $$

**Step 2: Calculate the distance for the second segment.**
The train travels at 40 mph for 1.5 hours.
$$ \text{Distance}_2 = \text{Speed} \times \text{Time} $$
$$ \text{Distance}_2 = 40 \text{ mph} \times 1.5 \text{ hours} = 60 \text{ miles} $$

**Step 3: Calculate the total distance.**
Add the distances from both segments.
$$ \text{Total Distance} = \text{Distance}_1 + \text{Distance}_2 $$
$$ \text{Total Distance} = 

qwen3.6:27b chain turn 2

The seasons on Earth are primarily caused by the planet's axial tilt of approximately 23.5 degrees relative to its orbital plane around the Sun. This tilt means that different hemispheres receive varying amounts of direct sunlight and daylight hours throughout the year as Earth revolves around the Sun. When a hemisphere is tilted toward the Sun, it experiences summer due to more direct solar radiation, while the hemisphere tilted away experiences winter.

qwen3.6:27b chain turn 3

Elias had watched the storm-tossed coast for thirty years, expecting nothing but driftwood and kelp. That morning, however, a glint of unnatural green light caught his eye among the jagged black stones. He knelt beside a small, glass bottle that hummed with a low, rhythmic vibration, far older than any shipwreck he had ever known. As he uncorked it, a whisper of salt air rushed out, carrying the voice of the first keeper who had tended this light centuries ago.

qwen3.6:27b chain turn 4

1. Keep functions small and focused on a single responsibility.
2. Use clear, descriptive names for variables, functions, and classes.
3. Write comprehensive tests to catch regressions early.
4. Document complex logic and decisions with concise comments or docstrings.
5. Follow consistent coding standards and formatting rules across the project.

battery-dflash — exit 1 seconds 7.1 status fail

reason: harness exit 1

no rows

chain-dflash — exit 1 seconds 7.1 status fail

reason: harness exit 1

no rows

ornith-1.5:35b-a3b-mq4r

source: bucket sha256_ok: ✅ size_ok: ✅ status: pass reason: battery-dflash: skipped (fixture ornith-1.5:35b-a3b-mq4r declares no dflash_draft); chain-dflash: skipped (fixture ornith-1.5:35b-a3b-mq4r declares no dflash_draft)

battery — exit 0 seconds 34.2 status pass

mode	idx	genre	finish	ctx	cached	gen	ans_words	prefill_tok_s	decode_tok_s	attractor	empty	runaway	recall_ok
battery	0		stop	34	0	160	79	412.9	23.0	False	False	False	True
battery	1		stop	30	0	101	90	485.0	92.7	False	False	False	True
battery	2		stop	31	0	16	13	441.4	131.3	False	False	False	True
battery	3		stop	47	0	31	8	628.4	123.4	False	False	False	True
battery	4		stop	47	0	17	7	647.2	75.4	False	False	False	True

ornith-1.5:35b-a3b-mq4r battery turn 0

```python
def longest_substring_without_repeating_chars(s: str) -> str:
    if not s:
        return ""
    
    char_index = {}  # character to its latest index
    max_length = 0
    start = 0  # start index of current window
    best_start = 0
    
    for end, char in enumerate(s):
        if char in char_index and char_index[char] >= start:
            start = char_index[char] + 1
        char_index[char] = end
        
        if end - start + 1 > max_length:
            max_length = end - start + 1
            best_start = start
    
    return s[best_start:best_start + max_length]
```

ornith-1.5:35b-a3b-mq4r battery turn 1

The sky appears blue during the day because sunlight interacts with Earth's atmosphere through a process called Rayleigh scattering, in which shorter blue wavelengths of light scatter more easily off air molecules than longer wavelengths. At sunset, the sun sits lower on the horizon, meaning its light must travel through a much greater thickness of atmosphere, causing most of the blue light to be scattered away before reaching your eyes. This leaves primarily the longer red and orange wavelengths to reach your eyes directly, producing the characteristic warm sunset colors.

ornith-1.5:35b-a3b-mq4r battery turn 2

The capital of France is Paris, and the River Seine runs through it.

ornith-1.5:35b-a3b-mq4r battery turn 3

{
  "name": "Alice",
  "age": 34,
  "city": "Lisbon"
}

ornith-1.5:35b-a3b-mq4r battery turn 4

17 + 26 = 43

Answer: 43

chain — exit 0 seconds 23.4 status pass

mode	idx	genre	finish	ctx	cached	gen	ans_words	prefill_tok_s	decode_tok_s	attractor	empty	runaway	recall_ok
chain	0		length	44	0	256	145	536.7	109.3	False	False	True	True
chain	1		stop	352	0	150	62	131.7	62.7	False	False	False	True
chain	2		stop	528	502	74	59	427.3	41.3	False	False	False	True
chain	3		stop	636	602	102	82	612.7	79.0	False	False	False	True
chain	4		stop	770	738	99	73	536.9	65.4	False	False	False	True

ornith-1.5:35b-a3b-mq4r chain turn 0

```python
def merge_sorted(a, b):
    """Merge two sorted lists into a single sorted list.

    Uses a two-pointer approach to combine `a` and `b` in O(n + m) time.
    Neither input is modified, and no built-in sort is used.
    """
    result = []
    i, j = 0, 0

    # Advance through both lists, appending the smaller element each time.
    while i < len(a) and j < len(b):
        if a[i] <= b[j]:
            result.append(a[i])
            i += 1
        else:
            result.append(b[j])
            j += 1

    # Copy whatever remains (at most one of the two sublists is non-empty).
    result.extend(a[i:])
    result.extend(b[j:])
    return result
```

**How it works:**
- Two pointers (`i`, `j`) track the current position in each list.
- At each step, the smaller of the two current elements is appended to `result`, and the corresponding pointer advances.
- When one list is exhausted, the remainder of the other is appended directly.

ornith-1.5:35b-a3b-mq4r chain turn 1

**Step 1: Distance for the first leg**

$$\text{Distance} = \text{Speed} \times \text{Time} = 60 \text{ mph} \times 2.5 \text{ hours} = 150 \text{ miles}$$

**Step 2: Distance for the second leg**

$$40 \text{ mph} \times 1.5 \text{ hours} = 60 \text{ miles}$$

**Step 3: Add the two legs together**

$$150 + 60 = 210 \text{ miles}$$

**Total distance traveled: 210 miles** ✅

ornith-1.5:35b-a3b-mq4r chain turn 2

The seasons are caused by the 23.5-degree tilt of Earth's axis relative to its orbit around the Sun. As Earth orbits the Sun over the course of a year, this tilt causes different hemispheres to receive varying amounts of direct sunlight. When one hemisphere is tilted toward the Sun, it experiences summer, while the opposite hemisphere simultaneously experiences winter.

ornith-1.5:35b-a3b-mq4r chain turn 3

Elias had tended the lighthouse for thirty years and thought he'd seen every secret the ocean chose to return. On a fog-chilled morning, he found a small wooden box wedged in the rocks, its surface carved with symbols he didn't recognize. Inside lay a cluster of glass vials, each holding a tiny, glowing light that flickered like a captured star. As he lifted one free, the water behind him began to boil without wind, and something below the surface began to rise.

ornith-1.5:35b-a3b-mq4r chain turn 4

1. Use clear, descriptive names for variables and functions so the intent is obvious at a glance.
2. Keep functions small and focused, ensuring each one does a single well-defined task.
3. Consistently follow the project's style and formatting conventions so the code looks uniform.
4. Write meaningful comments only where the reasoning isn't self-evident from the code itself.
5. Avoid duplicating logic by extracting shared behavior into reusable helpers when patterns repeat.

battery-dflash — exit 0 seconds 0.0 status skip

reason: fixture ornith-1.5:35b-a3b-mq4r declares no dflash_draft

no rows

chain-dflash — exit 0 seconds 0.0 status skip

reason: fixture ornith-1.5:35b-a3b-mq4r declares no dflash_draft

no rows

lfm2.5:1.2b

source: bucket sha256_ok: ✅ size_ok: ✅ status: pass reason: battery-dflash: skipped (fixture lfm2.5:1.2b declares no dflash_draft); chain-dflash: skipped (fixture lfm2.5:1.2b declares no dflash_draft)

battery — exit 0 seconds 8.0 status pass

mode	idx	genre	finish	ctx	cached	gen	ans_words	prefill_tok_s	decode_tok_s	attractor	empty	runaway	recall_ok
battery	0		stop	0	0	119	58	None	224.11	False	False	False	True
battery	1		stop	0	0	62	55	None	227.11	False	False	False	True
battery	2		stop	0	0	18	16	None	230.77	False	False	False	True
battery	3		stop	0	0	26	8	None	230.09	False	False	False	True
battery	4		stop	0	0	21	13	None	228.26	False	False	False	True

lfm2.5:1.2b battery turn 0

```python
def longest_unique_sub(s):
    seen = {}
    start = 0
    max_length = 0
    max_sub = ""
    for i, char in enumerate(s):
        if char in seen and start <= seen[char]:
            start = seen[char] + 1
        else:
            if i - start + 1 > max_length:
                max_length = i - start + 1
                max_sub = s[start:i+1]
        seen[char] = i
    return max_sub
```

lfm2.5:1.2b battery turn 1

The sky appears blue during the day because sunlight interacts with gases in the atmosphere, scattering shorter blue wavelengths more effectively. At sunset, the sunlight travels through a longer path of the Earth's atmosphere, causing more scattering of red and orange wavelengths. This results in the vibrant red colors we see as the sun sets.

lfm2.5:1.2b battery turn 2

The capital of France is Paris, and the river that runs through it is the Seine.

lfm2.5:1.2b battery turn 3

{
  "name": "Alice",
  "age": 34,
  "city": "Lisbon"
}

lfm2.5:1.2b battery turn 4

We add the two numbers together: 17 + 26 = 43.  
Answer: 43

chain — exit 0 seconds 13.5 status pass

mode	idx	genre	finish	ctx	cached	gen	ans_words	prefill_tok_s	decode_tok_s	attractor	empty	runaway	recall_ok
chain	0		stop	0	0	188	96	None	160.14	False	False	False	True
chain	1		stop	0	0	139	87	None	165.48	False	False	False	True
chain	2		stop	0	0	63	55	None	158.69	False	False	False	True
chain	3		stop	0	0	91	70	None	153.2	False	False	False	True
chain	4		stop	0	0	71	54	None	154.01	False	False	False	True

lfm2.5:1.2b chain turn 0

```python
def merge_sorted(a, b):
    """
    Merges two already-sorted lists into a single sorted list without using sorted().

    Args:
        a (list): First sorted list.
        b (list): Second sorted list.

    Returns:
        list: A new list containing elements from both a and b in sorted order.
    """
    merged = []
    i, j = 0, 0

    # Traverse both lists and append smaller element to merged
    while i < len(a) and j < len(b):
        if a[i] < b[j]:
            merged.append(a[i])
            i += 1
        else:
            merged.append(b[j])
            j += 1

    # Append remaining elements from a or b
    merged.extend(a[i:])
    merged.extend(b[j:])

    return merged
```

lfm2.5:1.2b chain turn 1

Let's break down the train's journey step by step.

### Step 1: Train travels at 60 mph for 2.5 hours
Distance = Speed × Time  
First segment:  
Distance�� = 60 mph × 2.5 hours = 150 miles

### Step 2: Train travels at 40 mph for 1.5 hours
Distance�� = 40 mph × 1.5 hours = 60 miles

### Total Distance
Total distance = Distance�� + Distance��  
= 150 miles + 60 miles = **210 miles**

### Final Answer:
The train traveled a total of **210 miles**.

lfm2.5:1.2b chain turn 2

The seasons on Earth are caused by the relative movement of the Earth and the Sun, as well as the tilt of the Earth's axis. When the Northern Hemisphere tilts toward the Sun, it experiences summer, while the Southern Hemisphere experiences winter. This changing angle of sunlight affects the length and intensity of the seasons.

lfm2.5:1.2b chain turn 3

One foggy evening, a young lighthouse keeper notices a strange, weathered object bobbing in the crashing waves near the rocks. Curious, he carefully collects the item, which turns out to be a beautifully preserved mermaid tail. As he examines it, he feels a sudden chill in the air and hears a faint whisper of sea stories. That night, he dreams of the sea's secrets, forever changed by the mysterious encounter.

lfm2.5:1.2b chain turn 4

1. Use clear and descriptive variable names to improve readability.  
2. Break your code into small, reusable functions for better organization.  
3. Write comments to explain complex logic for other developers.  
4. Regularly test your code to catch errors early and maintain stability.  
5. Follow consistent naming conventions and style guidelines throughout your project.

battery-dflash — exit 0 seconds 0.0 status skip

reason: fixture lfm2.5:1.2b declares no dflash_draft

no rows

chain-dflash — exit 0 seconds 0.0 status skip

reason: fixture lfm2.5:1.2b declares no dflash_draft

no rows

qwen3.8:27b-mq4-xt

source: bucket sha256_ok: ✅ size_ok: ✅ status: fail reason: battery-dflash: harness exit 1; chain-dflash: harness exit 1

battery — exit 0 seconds 19.6 status pass

mode	idx	genre	finish	ctx	cached	gen	ans_words	prefill_tok_s	decode_tok_s	attractor	empty	runaway	recall_ok
battery	0		stop	34	0	132	62	301.5	28.2	False	False	False	True
battery	1		stop	30	0	100	80	417.9	48.3	False	False	False	True
battery	2		stop	31	0	19	16	430.6	48.5	False	False	False	True
battery	3		stop	47	0	22	6	478.1	48.4	False	False	False	True
battery	4		stop	47	0	17	7	479.7	48.5	False	False	False	True

qwen3.8:27b-mq4-xt battery turn 0

```python
def longest_substring_without_repeating(s: str) -> str:
    char_index = {}
    start = 0
    max_length = 0
    max_start = 0
    
    for end, char in enumerate(s):
        if char in char_index and char_index[char] >= start:
            start = char_index[char] + 1
        char_index[char] = end
        if end - start + 1 > max_length:
            max_length = end - start + 1
            max_start = start
    
    return s[max_start:max_start + max_length]
```

qwen3.8:27b-mq4-xt battery turn 1

Sunlight, which contains all visible colors, enters Earth's atmosphere where gas molecules scatter shorter-wavelength blue light much more effectively than longer-wavelength red light, a process known as Rayleigh scattering. During the day, when the sun is high, we see this scattered blue light coming from all directions in the sky. At sunset, sunlight travels through a much longer path of atmosphere, scattering away almost all the blue light and leaving the less-scattered red and orange wavelengths to dominate the view.

qwen3.8:27b-mq4-xt battery turn 2

The capital of France is Paris, and the river that runs through it is the Seine.

qwen3.8:27b-mq4-xt battery turn 3

{"name": "Alice", "age": 34, "city": "Lisbon"}

qwen3.8:27b-mq4-xt battery turn 4

17 + 26 = 43

Answer: 43

chain — exit 0 seconds 21.2 status pass

mode	idx	genre	finish	ctx	cached	gen	ans_words	prefill_tok_s	decode_tok_s	attractor	empty	runaway	recall_ok
chain	0		stop	44	0	116	47	386.9	48.3	False	False	False	True
chain	1		stop	216	161	234	122	392.8	48.3	False	False	False	True
chain	2		stop	476	451	97	84	276.9	48.3	False	False	False	True
chain	3		stop	607	574	133	105	295.1	48.2	False	False	False	True
chain	4		stop	772	741	73	54	336.3	48.1	False	False	False	True

qwen3.8:27b-mq4-xt chain turn 0

```python
def merge_sorted(a, b):
    """Merge two already-sorted lists into one sorted list."""
    i = 0
    j = 0
    result = []
    while i < len(a) and j < len(b):
        if a[i] <= b[j]:
            result.append(a[i])
            i += 1
        else:
            result.append(b[j])
            j += 1
    result.extend(a[i:])
    result.extend(b[j:])
    return result
```

qwen3.8:27b-mq4-xt chain turn 1

To find the total distance traveled, we need to calculate the distance for each segment of the trip and then add them together. The formula for distance is:

$$ \text{Distance} = \text{Speed} \times \text{Time} $$

**Step 1: Calculate the distance for the first segment**
*   Speed: 60 mph
*   Time: 2.5 hours
*   Distance $d_1 = 60 \times 2.5 = 150$ miles

**Step 2: Calculate the distance for the second segment**
*   Speed: 40 mph
*   Time: 1.5 hours
*   Distance $d_2 = 40 \times 1.5 = 60$ miles

**Step 3: Calculate the total distance**
*   Total Distance $= d_1 + d_2$
*   Total Distance $= 150 + 60 = 210$ miles

**Final Answer:**
The train traveled a total of **210 miles**.

qwen3.8:27b-mq4-xt chain turn 2

The seasons on Earth are primarily caused by the planet's axial tilt of approximately 23.5 degrees relative to its orbital plane around the Sun. As Earth orbits the Sun, this tilt causes different hemispheres to receive varying angles and durations of sunlight throughout the year, leading to longer days and higher solar intensity in one hemisphere while the other experiences shorter days and lower intensity. This differential exposure to solar radiation creates the alternating patterns of warming and cooling that we recognize as seasons.

qwen3.8:27b-mq4-xt chain turn 3

Elias wiped the salt spray from the lantern glass when he heard the rhythmic thud of debris hitting the jagged shore below. He hurried down the spiral stairs, his heart pounding not from exertion but from the peculiar glint he caught in the moonlight on the black rocks. There, wedged between the barnacles and seaweed, was not a broken plank or a rusted buoy, but a pristine, unopened letter bearing his own name in his late wife’s handwriting. He stood frozen in the brine-soaked cold, tears mixing with the salt on his face, knowing with terrifying certainty that she had passed away forty years prior.

qwen3.8:27b-mq4-xt chain turn 4

1. Write clear, descriptive variable and function names that explain their purpose.
2. Keep functions small and focused on a single responsibility.
3. Use consistent formatting and adhere to established style guides.
4. Add concise comments to explain complex logic or non-obvious decisions.
5. Write automated unit tests to verify functionality and prevent regressions.

battery-dflash — exit 1 seconds 7.1 status fail

reason: harness exit 1

no rows

chain-dflash — exit 1 seconds 7.1 status fail

reason: harness exit 1

no rows

kernel

status: pass

report pass: True

[hipfire-sol]

hw-gate sol verdict

{
  "claim_verdict": "disproven",
  "confidence": 0.98,
  "coverage": {
    "gaps": [
      "No successful DFlash generation route evidenced speculative decode, context-exhaustion handling, or emitter-error rollback.",
      "No fault-injection evidence covered transactional GPU allocation rollback or sticky 700/719 poisoning.",
      "No multi-GPU EP/PP route exercised the new admission and DeviceMesh topology behavior.",
      "Registry pull/rm sidecar lifecycle and policy changes were not exercised end to end.",
      "The gfx12/hiptrx lane timed out or failed every fixture route after about 198 seconds, and its Redline run timed out on a subsequent load despite an internally passing first report.",
      "No successful MQ4-V2 parity run covered the changed gfx12 dispatch-sensitive surface."
    ],
    "surfaces_evidenced": [
      "kernel",
      "load",
      "serve",
      "prompt-cache"
    ],
    "surfaces_touched": [
      "kernel",
      "load",
      "serve",
      "prompt-cache",
      "speculative-decode",
      "rollback",
      "multi-gpu-topology",
      "registry-policy",
      "config",
      "filesystem",
      "docs"
    ]
  },
  "decision": "block",
  "eyeball": [
    "qwen3.8:27b-mq4-xt gfx1100 chain: responses are semantically coherent, but all five turns report cached=0, directly disproving the central cache-hit claim.",
    "qwen3.6:27b gfx1100 chain: later turns show substantial cache hits, demonstrating that the harness can observe working prefix caching.",
    "lfm2.5:1.2b gfx1100 chain turn 2: inspect the repeated `Distance\ufffd\ufffd` replacement characters.",
    "All hiptrx fixture routes should be inspected as infrastructure or device-selection failures: coherent rows were produced, but every route ended with exit 1 after roughly 198 seconds.",
    "The paired-Qwen DFlash logs need inspection because both models failed before emitting a single decoded row."
  ],
  "phase": "verdict",
  "rationale": "Block: the central Qwen3.8 claim is directly disproven by the gfx1100 chain, where cached remained zero after turn one. Both Qwen DFlash routes also failed with no output, and the mandatory kernel lane is globally failed because hiptrx timed out during load. Although the gfx1100 Redline report showed stable sequences and exact HIP/AQL/PM4 parity, substantial rollback, topology, policy, DFlash, and gfx12 coverage remains absent.",
  "regressions": [
    {
      "beta_behavior": "The advertised template-aware primer probe did not restore caching on the tested Qwen3.8 fixture: every turn in the gfx1100 qwen3.8:27b-mq4-xt chain reported cached=0.",
      "evidence": "hipx/gfx1100 qwen3.8:27b-mq4-xt chain: cached values were 0,0,0,0,0, while the qwen3.6:27b control produced later-turn cache hits of 160/44/579/720. This directly contradicts the claimed Qwen3.8 cache restoration.",
      "file": "crates/hipfire-runtime/src/prompt_frame.rs",
      "line": 1498,
      "master_behavior": "Qwen3.8 multi-turn Jinja replay should extend the prior prompt-cache prefix after turn one.",
      "severity": "high"
    },
    {
      "beta_behavior": "Both paired Qwen fixtures failed before producing any DFlash rows.",
      "evidence": "hipx qwen3.6:27b battery-dflash and chain-dflash exited 1 after about 7.1 seconds with zero rows; qwen3.8:27b-mq4-xt did the same. The ordinary AR battery and chain routes passed on the same lane.",
      "file": "crates/hipfire-generate/src/qwen.rs",
      "line": 2204,
      "master_behavior": "A registry-paired DFlash model should load and complete battery and chain generation when explicitly tested with DFlash.",
      "severity": "high"
    },
    {
      "beta_behavior": "The LFM chain emitted Unicode replacement characters inside otherwise ordinary mathematical labels.",
      "evidence": "hipx lfm2.5:1.2b chain turn 2 contains repeated `Distance\ufffd\ufffd` text. The harness marked the route pass, but decoded replacement characters are a coherence failure under the hardware-gate eyeball rule.",
      "file": "crates/hipfire-runtime/src/prompt_frame.rs",
      "line": 1498,
      "master_behavior": "Decoded multi-turn output should remain valid text.",
      "severity": "medium"
    }
  ]
}

Floor: hard=['hw_run_result=failure', "evidence verdict='fail'", 'kernel status != pass', 'policy_paths: registry/models.json,registry/v1.json,scripts/leanup-thresholds.txt'] soft=["coverage_gaps: ['No successful DFlash generation route evidenced speculative decode, context-exhaustion handling, or emitter-error rollback.', 'No fault-injection evidence covered transactional GPU allocation rollback or sticky 700/719 poisoning.', 'No multi-GPU EP/PP route exercised the new admission and DeviceMesh topology behavior.', 'Registry pull/rm sidecar lifecycle and policy changes were not exercised end to end.', 'The gfx12/hiptrx lane timed out or failed every fixture route after about 198 seconds, and its Redline run timed out on a subsequent load despite an internally passing first report.', 'No successful MQ4-V2 parity run covered the changed gfx12 dispatch-sensitive surface.']"] model_decision=block final=block

[Kaden-Schutt]

Correcting the finding on this PR, because the record as it stands points at the wrong defect.

I pulled the serve log from the run that produced it (gate run 33907487315, fable-evidence/dflash-chain-qwen36-serve.log). In order:

[qwen-cache store dflash]  fp=0xb8df43230469ae1b cached_seq=1485
[qwen-cache lcp dflash-jinja] prior_len=1528 rendered_len=1582 lcp=1528
[qwen-cache HIT dflash] reuse prefix=1528 suffix=54 (no reset)
[qwen-cache store dflash]  fp=0xd7a7d25bf966ba4c cached_seq=683
[qwen-cache lcp dflash-jinja] prior_len=2266 rendered_len=2290 lcp=2266
[qwen-cache HIT dflash] reuse prefix=2266 suffix=24 (no reset)
spec_prefix_realign: HipError(719): hipMemcpy H2D offset: unspecified launch failure
[qwen-cache jinja lookup dflash] fp=0xb8df... hit=false
[qwen-cache jinja lookup dflash] fp=0xd7a7... hit=false
prefill: HipError(719): hipMemsetAsync: unspecified launch failure (reset_recurrent: qwen3…)   ×3

lcp == prior_len on every hit — full-prefix reuse, suffix=54 then suffix=24, no reset. There is no stored + 2 slack in the log, and the later lookups are hit=false outright rather than partial LCPs.

So the "primer replay systematically misses the most recent assistant body" reading does not survive its own evidence: the ordering shows the HipError(719) comes first and the misses follow it. 719 is hipErrorLaunchFailure — sticky and context-killing — so once it fires, every subsequent lookup legitimately misses and no amount of reset_recurrent can recover.

That makes the real work here:

1. spec_prefix_realign's H2D copy faulting. The usual cause of a sticky 719 is a launch against a pointer that has been freed or reallocated. We hit that exact class twice tonight in sibling PRs — dangling kernargs after a rollback (fix(dflash): transactional draft ctors, emitter-error rollback, one ctx-cap predicate #691) and a VRAM pool never drained on a refused load (feat(dflash): registry-declared draft sidecars — pull fetches, auto uses, on requires #686). Worth asking whether the realign path assumes device state that a cache HIT reusing a prefix (no reset) never re-established.
2. The retry loop. After a sticky 719 the context is dead, yet the daemon retried three more times and produced three more 719s. Failing the request closed on the first sticky error is a correctness fix independent of the root cause.

The AR half is unaffected and was already proven on both lanes. An agent is on (1) and (2) now; I'll post what it finds. Config for the record: qwen3.6-27b, DFlash on, ChatML, thinking on with non-empty reasoning_content, tool_calls=0.

[hipfire-sol]

hw-gate sol verdict needs-human: All executed fixtures passed on gfx1201 and gfx1100, decoded text is coherent, qwen3.8 AR chains demonstrate the intended cache extension, and qwen3.6 controls show no observed template regression. Redline also reports stable captures and exact HIP/blob/AQL state parity. However, the branch additionally changes DFlash replay, daemon-wide sticky GPU-fault state, plain-Llama MQ-V2 admission, and benchmark CLI behavior without direct evidence for those paths. The central AR fix is supported, but the author's AR-and-DFlash equivalence claim is not fully exercised, so the state-machine and speculative-decode coverage gaps require human disposition.

[Kaden-Schutt]

Merged to beta as acae74dd4 (branch tip fa30b3ae2).

Run 33934632513: both lanes pass at 370592d17 (hiptrx gfx1201 + hipx gfx1100, verdict: pass, zero non-pass modes), Sol needs-human with zero regressions, Fable unavailable (credits) — so this staging merge is mine, not the seat's, and master stays human-promoted.

The finding that held this PR was misdiagnosed, and its own log settles it — full detail in the comment above. Short version: lcp == prior_len on every hit, so primer replay was never missing the assistant body; a sticky HipError(719) in the windowed draft_seed_backfill H2D upload came first, and the hit=false lookups after it are the rollback clearing asst_turn_cache working as designed.

What landed on top is the fix that is correct regardless of the 719's root cause: the first sticky fault is now the last. 700/719 latch a first-wins GpuPoison in reset_core.rs, the qwen35 reset/prefill error sites latch on the typed HipError (no string sniffing), and the daemon fails fast pre-generate with class gpu, non-retryable, "process restart required". The latch never auto-clears, because a model reload does not reset the primary HIP context — clearing it would just burn one prefill per reload.

600 tests in hipfire-runtime and 189 in hipfire-arch-qwen35, including sticky_poison_latch_lifecycle.

Still open and recorded rather than invented: the 719 itself needs a device-sync bisection across the backfill chunk ops, plus a pointer-lifetime trace on draft_scratch.{target_hidden,k_full,v_full,positions_k} across a HIT → realign. That is hardware work; I have the hosts when you want it.

[hipfire-sol]

hw-gate sol verdict block: Block: the central Qwen3.8 claim is directly disproven by the gfx1100 chain, where cached remained zero after turn one. Both Qwen DFlash routes also failed with no output, and the mandatory kernel lane is globally failed because hiptrx timed out during load. Although the gfx1100 Redline report showed stable sequences and exact HIP/AQL/PM4 parity, substantial rollback, topology, policy, DFlash, and gfx12 coverage remains absent.