Laguna-S-2.1 · Winnow keep-50
poolside/Laguna-S-2.1 (118B-A8B)
with
50% of routed-expert channels removed by
winnow
variable-width expert pruning —
60.8B parameters, no healing/retraining.
Instead of deleting whole experts (REAP-style), winnow shrinks each expert's
SwiGLU intermediate width according to a per-channel importance score
(router_weight × |post-SwiGLU activation| × down-projection column L2),
allocated by a per-layer global rank. 80% of experts survive at reduced,
ragged widths; the shared expert, attention, and embeddings are untouched.
Scoring, pruning, and evaluation all ran
layer-streamed on 3×RTX 3090
(the source model never fit in memory): one decoder layer resident per GPU,
residual streams ping-ponged through disk, calibration data-parallel across
GPUs. Calibration: 2.1M tokens of
bigcode/the-stack-smol.
Results (unhealed)
| model | params | held-out code ppl | HumanEval pass@1 |
|---|
| Laguna-S-2.1 (base) | 118B | 2.947 | — |
| keep-75 (here) | 89.2B | 2.980 (+1.1%) | — |
| keep-50 (this repo) | 60.8B | 3.399 (+15.3%) | 89.6% |
- Perplexity: 64 held-out the-stack-smol sequences (2048 tokens each), identical
ruler for all three rows, computed layer-streamed.
- HumanEval: greedy, chat-extract protocol, thinking disabled, max 1280 new
tokens, INT8-expert serving. Not comparable to raw-completion HumanEval
numbers or to poolside's published agentic benchmarks (SWE-bench,
Terminal-Bench 2.1), which use a different harness and far larger budgets.
- Qualitative agentic check: with a 16k serving context the model autonomously
solved several classic Terminal-Bench 1.0 core tasks end-to-end on the same
3×3090 host; most failures were context exhaustion, not task competence.
Serving
At INT8 W8A16 expert weights this model serves on
3×24GB GPUs via the
winnow vLLM plugin (ragged experts
are not representable in stock FusedMoE):
1vllm serve hbfreed/Laguna-S-2.1-winnow-keep50 \
2 --enforce-eager --pipeline-parallel-size 3 --quantization experts_int8 \
3 --max-model-len 16384
Measured on 3×3090: 34 tok/s single-stream, ~150 tok/s at batch 8.
Tensor parallelism is unsupported (packed ragged weights don't shard);
pipeline parallelism is the intended mode.
Reference (unfused) loading works with plain transformers ≥ 5.13:
1from transformers import AutoModelForCausalLM
2model = AutoModelForCausalLM.from_pretrained(
3 "hbfreed/Laguna-S-2.1-winnow-keep50", trust_remote_code=True)
winnow.json records the full pruning plan, calibration provenance, and
per-expert channel indices.
Pruned with winnow's
stream-prune; see the winnow repository for the method
writeup. Base model by
poolside, released under
OpenMDW-1.1; this derivative keeps that license.