IQuest-Loop-Instruct GGUF Conversion Summary
Date: 2026-01-07 Model: IQuestLab/IQuest-Coder-V1-40B-Loop-Instruct Achievement: World's first IQuest-Loop-Instruct GGUF conversion
Files Created
| File | Size | Format | SHA256 | Completion Time |
|---|---|---|---|---|
| IQuest-Coder-V1-40B-Loop-Instruct-f16.gguf | 75GB | F16 | b70d3bb48753e786c8afca7556b818341fc9258e29083be4b0375c5a8b788289 |
2m 6s |
| IQuest-Coder-V1-40B-Loop-Instruct-q4_k_m.gguf | 23GB | Q4_K_M | b665999c8d6660ba0ea29cbbb072056052ef965a233ef65661ec16a16b39a9e3 |
2m 23s |
| IQuest-Coder-V1-40B-Loop-Instruct-q5_k_m.gguf | 27GB | Q5_K_M | a15814998038c8c6334f69bc11b776bce785350c933ce95fe9c41c4c7ec708ba |
1m 41s |
| IQuest-Coder-V1-40B-Loop-Instruct-q8_0.gguf | 40GB | Q8_0 | a9323b7ca583a842737dd4ec1f7422101c68ededf2a86c75a8d5e9da70eaae06 |
53s |
Technical Implementation
Architecture Support
Created IQuestLoopCoderModel class in llama.cpp's convert_hf_to_gguf.py:
- Inherits from
LlamaModel(compatible architecture base) - Maps 160 loop-specific
gate_projectionstensors to GGUF format - Preserves loop parameters in metadata:
llama.loop.num: 2llama.loop.window_size: 64
Tensor Mapping
Gate Projections (160 tensors total):
- Source:
model.gate_projections.{0-79}.{weight|bias} - Shape:
[128, 40]weight +[40]bias per layer - Target:
blk.{layer}.loop_gate.{weight|bias} - Quantization: Uses fallback q5_0/q5_1 for Q4_K_M/Q5_K_M (tensors too small for standard quantization)
Standard Tensors (721 tensors):
- Uses LlamaModel's standard tensor mapping
- Attention: Q, K, V, Output projections
- FFN: Gate, Up, Down projections
- Normalization: Attention & FFN RMS norms
Conversion Statistics
- Total Tensors: 883
- Standard Llama: 721
- Loop Gates: 160 (80 layers × 2 per layer)
- Embeddings: 2
- Vocabulary Size: 76,800 tokens
- Context Length: 131,072 tokens
- Hidden Layers: 80
- Attention Heads: 40 (8 KV heads)
- Hidden Size: 5,120
- FFN Size: 27,648
Current Status
What Works ✅
- Conversion: Successfully converts HuggingFace → GGUF F16
- Quantization: All standard quantization levels work (Q4_K_M, Q5_K_M, Q8_0, etc.)
- Metadata: Loop parameters correctly stored in GGUF metadata
- Tensor Preservation: All 883 tensors including loop gates successfully converted
- Ollama Import: Ollama accepts and imports the GGUF file
What Needs Work 🔧
- Runtime Support: llama.cpp runtime needs loop attention mechanism implementation
- Inference: Model loads but cannot run inference yet (loop gates not used)
- Testing: Need to validate loop attention behavior matches original PyTorch
Implementation Details
Modified Files
/tmp/convert_hf_to_gguf.py (lines 2695-2733):
@ModelBase.register("IQuestLoopCoderForCausalLM")
class IQuestLoopCoderModel(LlamaModel):
"""IQuest Loop Coder model with recurrent loop attention mechanism."""
model_arch = gguf.MODEL_ARCH.LLAMA
def __init__(self, *args, **kwargs):
super().__init__(*args, **kwargs)
self.loop_num = self.hparams.get('loop_num', 2)
self.loop_window_size = self.hparams.get('loop_window_size', 64)
def set_gguf_parameters(self):
super().set_gguf_parameters()
self.gguf_writer.add_uint32("llama.loop.num", self.loop_num)
self.gguf_writer.add_uint32("llama.loop.window_size", self.loop_window_size)
def modify_tensors(self, data_torch: Tensor, name: str, bid: int | None):
if "gate_projections" in name:
parts = name.split('.')
if len(parts) >= 4 and parts[1] == "gate_projections":
layer_num = parts[2]
param_type = parts[3]
new_name = f"blk.{layer_num}.loop_gate.{param_type}"
return [(new_name, data_torch)]
return super().modify_tensors(data_torch, name, bid)
Next Steps for Community
For llama.cpp Maintainers
Implement Loop Attention Runtime:
- Read
llama.loop.numandllama.loop.window_sizefrom GGUF metadata - Load
blk.{layer}.loop_gate.{weight|bias}tensors - Implement recurrent loop attention mechanism in CUDA/CPU kernels
- Reference: Original implementation at IQuestLab/IQuest-Coder-V1-40B-Loop-Instruct
- Read
Add Unit Tests:
- Verify tensor loading
- Validate loop parameter reading
- Test against PyTorch reference implementation
Documentation:
- Add Loop architecture to supported models list
- Document loop parameter usage
- Provide conversion examples
For Model Users
- Wait for Runtime Support: These GGUFs will work once llama.cpp implements loop attention
- Use Regular Variant: For immediate use, IQuest-Coder (non-Loop) is fully supported
- Contribute: Help implement loop attention in llama.cpp runtime
Performance Expectations (Once Runtime Supports Loop)
Based on quantization levels:
- Q4_K_M (23GB): Recommended for most deployments, 30% of original size
- Q5_K_M (27GB): Better quality, 35% of original size
- Q8_0 (40GB): Excellent quality, 53% of original size, minimal loss
- F16 (75GB): Full precision reference
Docker Build System
Image: avarok/dgx-spark-complete:latest
Base: dgx-vllm:cutlass-nvfp4-v15
Includes:
- vLLM v15 with IQuest Loop Coder support
- llama.cpp with CUDA support
- Conversion scripts (convert_to_gguf.sh, quantize.sh)
- Optimized for NVIDIA GB10 (SM 12.1)
References
- Original Model: https://huggingface.co/IQuestLab/IQuest-Coder-V1-40B-Loop-Instruct
- llama.cpp Issue: #18517 - Request for Loop-Instruct support
- PR Inspiration: #18524 - Regular IQuestCoder support
- Debugging Journey: /workspace/builds/DEBUGGING_JOURNEY.md
Credits
- Hardware: Dual NVIDIA DGX Spark with GB10 GPUs
- Model: IQuestLab team for Loop architecture innovation
- Tools: llama.cpp (ggerganov), vLLM team
- First GGUF: This conversion is the first Loop-Instruct variant in GGUF format
Verification
SHA256 checksums provided for all files. Verify before use:
sha256sum IQuest-Coder-V1-40B-Loop-Instruct-*.gguf
Status: Conversion successful, runtime support pending Date: 2026-01-07 Next: Submit PR to llama.cpp with implementation + publish to HuggingFace