/evaluations/qwen35-4b
Qwen3.5-4B
Qwen3.5-4B — the current WumboLabs evidence state on one page: tested profiles, validated context, and the full chronological testing history. Each value is attributed to the profile and event that measured it.
/ latest evidence 2026-09-11
WumboLabs tests Qwen3.5-4B on real consumer hardware. This is the canonical model page: current state first, then every tested profile and every evidence event. Values are attributed to the profile and event that measured them; historical findings remain the evidence of their tested stack and are never silently replaced.
Current state
- Recommended profile: llama.cpp BF16 GGUF (
qwen35-4b-llamacpp-bf16, current) — canonical evidence - Practical context: 32,768 default / 65,536 guarded tokens; native model-card maximum 262,144 (envelope complete: YES) — Context envelope completion (2026-09-11)
- Latest evidence: 2026-09-11 — Context envelope completion
Tested profiles
llama.cpp BF16 GGUF — CURRENT
Profile identity: qwen35-4b-llamacpp-bf16.
| Field | Value |
|---|---|
| Runtime | llama.cpp 0.1.0-dev build b10449, commit 0d9ceae1e38291035605613ab41a8f5e693d6fcd (CUDA 13.3, SM120) |
| Artifact | Qwen3.5-4B-BF16.gguf (text-only conversion; Unsloth revision e87f176479d0855a907a41277aca2f8ee7a09523) |
| Precision | BF16 weights; f16 KV (primary surface); q4_0 KV (one alternate admission surface) |
Status: current canonical/recommended tested surface.
Canonical Evidence Profile Metadata
Events on this profile:
- Context envelope completion (2026-09-11) — READY_WITH_GUARDRAILS
Testing history
Newest first. Each event is one immutable testing/publication event; the exact scientific report lives in the canonical evidence repository linked at the top of each event.
2026-09-11 — Context envelope completion
Context Envelope — llama.cpp BF16 · profile: llama.cpp BF16 GGUF · maturity: CONTEXT_COMPLETION · status: READY_WITH_GUARDRAILS
Canonical Evidence / Full Report View on GitHub
Identity
| Field | Value |
|---|---|
| Model | Qwen3.5-4B |
| Producer | Alibaba (Qwen team); GGUF conversion by Unsloth |
| Official model | Qwen/Qwen3.5-4B @ 851bf6e806efd8d0a36b00ddf55e13ccb7b8cd0a |
| Tested artifact | Qwen3.5-4B-BF16.gguf (text-only conversion; Unsloth revision e87f176479d0855a907a41277aca2f8ee7a09523) |
| Precision | BF16 weights; f16 KV (primary surface); q4_0 KV (one alternate admission surface) |
| Artifact SHA-256 | 9e6e2841a75f503ccb330831832fd7861266e187e0dbf149a954219ccb8c197a |
| Campaign | qwen35-4b-rtx5070-context-completion-2026-09-11 |
| Record date | 2026-09-09 |
Runtime and hardware
| Field | Value |
|---|---|
| Engine | llama.cpp |
| Runtime version | 0.1.0-dev build b10449, commit 0d9ceae1e38291035605613ab41a8f5e693d6fcd (CUDA 13.3, SM120) |
| Runtime notes | All 33/33 runtime layers GPU-resident; non-thinking text-only greedy surface; identical inherited baseline stack |
| Hardware | WumboJetsII (NVIDIA GeForce RTX 5070 12GB) |
| Hardware notes | Single-user workstation; AMD Ryzen 7 9800X3D; Fedora Linux |
WELP outcome
- Outcome: PASS — QWEN35_4B_CONTEXT_ENVELOPE_COMPLETED
- Classification: READY_WITH_GUARDRAILS (unchanged; new occupancy-dependent instruction-retention guardrail added)
- Artifact classification: Comfortable-fit high-precision BF16 text control
Publication state: published — canonical evidence: https://github.com/WumboLabs/evaluations/blob/479cb50c197f8ea0dd905a68ffd61f632f49c652/models/qwen35-4b/events/context-envelope-completion-2026-09-11-qwen35-4b/REPORT.md
Context profile
| Field | Value |
|---|---|
| Practical default | 32768 tokens |
| Guarded context | 65536 tokens |
| Native model-card maximum | 262144 tokens |
| Model-card envelope complete | YES |
| Native maximum disposition | FIT_LIMIT - native maximum 262,144 on the BF16/f16 primary surface (arithmetic lower bound) and on the authorized q4_0-KV alternate surface (measured admission failure); official YaRN 1,010,000 maximum FIT_LIMIT at every representable KV precision |
Headline performance
| Surface | TTFT | Prefill | Decode |
|---|---|---|---|
| Short | 0.040569 s | — | 67.91 tok/s |
| Moderate (3642-token input) | 0.691319 s | 5268.19 tok/s | 67.29 tok/s |
Near-full context fixture medians per seed pair; client/transport proxies with native timings retained in campaign evidence; short/moderate surfaces inherited unchanged from the baseline campaign (67.9 tok/s short decode, 0.69 s moderate TTFT)
Quality and capabilities
- Constrained result: inherited: 7/7 constrained checks and 20/20 bounded reliability (baseline campaign, unchanged, not rerun)
- Perfect synthetic retrieval (20/20 values) at 99.4-99.5% occupancy through 64K on the primary surface
- Highest measured/admitted near-full primary context 65,536 (guarded profile confirmed); 98,304 projected below the frozen operational safety floor and intentionally not launched; exact ceiling not bracketed
- q4_0-KV alternate surface functionally correct at 32K
- Official YaRN mechanism representable in the pinned runtime
Guardrails and limitations
- Near-full-occupancy instruction retention defect: auxiliary JSON fields (synthesis/absent/checksum) dropped at both rungs, both seeds; do not place binding output instructions at extreme occupancy
- Inherited free-form grounding cautions unchanged
- Exact native maximum and YaRN maximum are unreachable on 12GB at any representable KV precision; not a model-capability claim on other hardware
Reliability: inherited bounded 20/20 reliability (profile unchanged); no new reliability run required; context-specific observations: zero CUDA/OOM/Xid events across all arms including the measured admission-failure attempt
LocalMaxxing
| Field | Value |
|---|---|
| Status | SUBMITTED |
| Canonical context | 32768 tokens |
| tok/s out | 68.0 |
| TTFT | 76.92 ms |
| Submission reference | cmtwcmm3207eqps01w7fubuuw |
| verifiedRun | NO |
origin VERIFIED_EXISTING (duplicate audit): canonical practical profile unchanged; no new benchmark, no duplicate submission
Canonical evidence
Canonical public evidence: https://github.com/WumboLabs/evaluations/blob/479cb50c197f8ea0dd905a68ffd61f632f49c652/models/qwen35-4b/events/context-envelope-completion-2026-09-11-qwen35-4b/REPORT.md
This event section is a human-readable derivative of the accepted local WELP campaign evidence named above; the campaign's REPORT.md is the authoritative scientific source. Results are bounded by the tested artifact, runtime, hardware, configuration, and protocol snapshot, and are not universal model rankings.
Canonical evidence
All canonical public evidence lives in WumboLabs/evaluations. Each event links an immutable full-commit/path citation; each profile remains a distinct scientific identity, not a separate repository.
- qwen35-4b-llamacpp-bf16: Profile Metadata