MAPLE: Manifold-Activated Pruning of Latent Experts | Aman Sachan

· Aman Sachan Research

5 min read Original article ↗

RESEARCH PREPRINT & OPEN-WEIGHTS RELEASE

Manifold-Activated Pruning of Latent Experts (MAPLE) compresses 128-expert fine-grained MoE architectures down to 4.75 GB (1.48 effective BPW), eliminating PCIe system-RAM paging stalls forever.

Throughput

6.57x speedup vs PCIe offload

Container Size

Sub-5GB (100% fits in 6GB VRAM)

Quantization

IQ2_XXS calibrated via imatrix

Expert Pruning

79.88% activation mass preserved

Hardware Benchmark Proof

Consumer laptops cannot run uncompressed 26B models without overflowing into system RAM over bandwidth-constrained PCIe lanes.

Inference Throughput (RTX 4050 6GB) 6.57x Real-World Lift

Base Gemma 4 26B IQ2_XXS (9.92 GB) 6.9 TPS (16/30 layers in VRAM)

14 layers offloaded to system RAM. Constrained by 15.75 GB/s PCIe bus bandwidth.

MAPLE 48-Expert Container (4.75 GB) 45.4 TPS (30/30 layers in VRAM)

100% In-VRAM execution. Dedicated 192 GB/s GDDR6 bus with zero host memory paging.

Test Rig RTX 4050 6GB Mobile

Context Window 2,048 Tokens

Host Memory Spills 0 Bytes (Zero Spill)

Precision & Accuracy Retention

Quality Retention (≥ 500 Tokens) Full benchmark completion & self-correction

100.0% Parity

Keyword & Syntax Fidelity Code generation & formal logic

93.8%

Activation Energy Retained Calibrated across Technical Corpus

79.88%

Effective Weight Precision Sub-2-BPW target architecture

1.48 BPW

Total Parameter Footprint Uncompressed 52GB -> MAPLE 4.75GB

10.9x Compression

Quality Parity: When the generation budget is set to 500+ tokens, MAPLE achieves 100% functional pass rate across syntax, logic, and data structure benchmarks with zero degradation compared to the unpruned base model.

Architectural Framing Domain-Targeted Pareto Distillation

We did not attempt lossy random pruning across the entire internet. Gemma 4 26B uses 128 fine-grained experts where massive clusters specialize in non-English languages, translation, and non-technical trivia. For edge code generation and technical deduction, those experts are dormant overhead.

MAPLE profiles the empirical activation manifold specifically on technical, algorithmic, and deductive tokens. We prune the 80 dormant experts and preserve the 48 active ones, masking excised router logits to -inf so softmax remains numerically stable.

Within the target domain (Python algorithmic synthesis, data structures, and logic), the model retains 100% functional unit-test execution when given standard token generation headroom (-n 512). The intentional trade-off is higher out-of-domain multilingual perplexity, which enables the model to run 100% inside 6GB VRAM at 45.4 TPS instead of stalling over PCIe at 6.9 TPS.

Architectural Foundation

Why naive expert removal destroys models, and how manifold activation analysis preserves technical reasoning.

Live Routing Profiling

MAPLE passes a multi-domain calibration corpus through Gemma 4, capturing exact token-to-expert router dispatch frequencies and activation magnitudes via llama-imatrix.

Dormant Expert Excision

80 dormant experts per layer are excised based on cumulative manifold energy thresholds. The router logits are dynamically re-indexed to dispatch across the 48 preserved experts.

GGUF Quantization Slicing

Preserved expert tensor slices are quantized into IQ2_XXS block representations using importance matrix weights, packaging the complete 26B model into a single 4.75 GB binary.

Empirical Reproducibility & Portability

Pruning follows your activation manifold. Understand why your workload yields your model, and how to adapt MAPLE to any Sparse MoE architecture.

Empirical Calibration Reality

Results Follow Your Calibration Corpus

MAPLE results are strictly deterministic and reproducible, but variable depending on your calibration dataset. What we released is a reference implementation on Gemma 4 26B-A4B optimized for edge technical execution.

Technical Specialization (Our Reference): Pruned 80 dormant experts, preserved 48 active ones. Reduced from 9.92 GB to 4.75 GB for 100% in-VRAM execution on 6GB GPUs.

General-Purpose Workloads: Calibrating on diverse multilingual dialogue activates a broad manifold. The optimizer may prune only 20 to 40 experts, retaining 88 to 108 experts for broad versatility.

Domain Customization: Biomedical, legal, or financial corpora activate entirely different expert clusters. If your workload is different, you get a different model.

"The reference Gemma 4 model proves the pipeline works. Your domain calibration produces your tailored edge container."

Universal SMoE Portability

Theoretically & Practically Universal Across All MoEs

Because MAPLE operates on fundamental router logits and activation variance, the mathematical formulation is directly portable to any Sparse Mixture-of-Experts transformer:

Liquid AI LFM 24B MoE

Mixtral 8x7B / 8x22B

DeepSeek-V2 / V3 MoE

Qwen 2.5 MoE (57B-A14B)

Any model using top-k router gating can be profiled via llama-imatrix or PyTorch forward hooks, sliced, and masked to -inf without retraining.

Universal Recipe How to Apply MAPLE to Any MoE Model (LFM-24B, Mixtral, DeepSeek)

01. CALIBRATE

Assemble 2k-10k tokens of domain text representing your target operational workload.

02. PROFILE

Run llama-imatrix to capture activation frequencies and channel energy matrix.

03. SCORE

Compute composite score s = C * sqrt(sigma + eps) and rank active experts per layer.

04. MASK -INF

Excise unselected expert tensors and set excised router logits to -inf for softmax invariance.

05. DEPLOY

Quantize via llama-quantize (IQ2_XXS / Q4_K_M) for 100% in-VRAM execution.

Instant Local Deployment

Native GGUF execution directly supported in llama.cpp, Ollama, and LM Studio.

llama-cli -hf AmSach/Gemma-4-26B-A4B-MAPLE-Sub5GB-GGUF -ngl 99 -c 2048 -n 512

-hf: Hugging Face repo auto-download

-ngl 99: Offload 100% of layers to GPU

-c 2048: 2k context window in 4.75GB

Verified Product & Community Showcases

Citation (BibTeX)

@article{sachan2026maple,
  title={MAPLE: Manifold-Activated Pruning of Latent Experts for Sub-2-BPW Mixture-of-Experts Language Models},
  author={Sachan, Aman},
  journal={Zenodo / CERN Open Science Preprint},
  year={2026},
  doi={10.5281/zenodo.24042480},
  url={https://doi.org/10.5281/zenodo.24042480}
}

@misc{sachan2026maple_kaggle,
  author={Sachan, Aman},
  title={MAPLE: Gemma 4 26B Sub-5GB MoE},
  publisher={Kaggle},
  year={2026},
  doi={10.34740/KAGGLE/M/786779},
  url={https://doi.org/10.34740/KAGGLE/M/786779}
}