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Gpt oss 120b

Model Overview

OpenAI’s GPT-OSS models (gpt-oss-120b & gpt-oss-20b) are open-weight models designed for powerful reasoning, agentic tasks and versatile developer use cases. GPT-OSS-120B is used for production, general purpose, high reasoning use cases that fit into a single 80GB GPU.

  • Model Architecture: 117B parameters with 5.1B active parameters. Trained on harmony response format and should only be used with the harmony format as it will not work correctly otherwise.
  • Model Source: openai/gpt-oss-120b
  • License: Apache 2.0 license. Build freely without copyleft restrictions or patent risk—ideal for experimentation, customization, and commercial deployment.
  • Configurable reasoning effort: Easily adjust the reasoning effort (low, medium, high) based on your specific use case and latency needs.
  • Full chain-of-thought: Gain complete access to the model’s reasoning process, facilitating easier debugging and increased trust in outputs. It’s not intended to be shown to end users.
  • Fine-tunable: Fully customize models to your specific use case through parameter fine-tuning.
  • Agentic capabilities: Use the models’ native capabilities for function calling, web browsing, Python code execution, and Structured Outputs.
  • Native MXFP4 quantization: The models were post-trained with MXFP4 quantization of the MoE weights, making gpt-oss-120b run on a single 80GB GPU.

QPC Configurations

Precision SoCs / Tensor slicing NSP-Cores (per SoC) Batch Size Chunking Prompt Length Context Length (CL) Generated URL Download
MXFP6 4 16 1 1 8192 https://qualcom-qpc-models.s3-accelerate.amazonaws.com/SDK1.20.2/openai/gpt-oss-120b/qpc_120b_ts4_cl8k_bs1_1spec_decode.tar.gz Download
MXFP6 8 16 1 1 8192 https://qualcom-qpc-models.s3-accelerate.amazonaws.com/SDK1.20.2/openai/gpt-oss-120b/qpc_120b_ts8_cl8k_bs1_1spec_decode.tar.gz Download
MXFP6 4 16 1 1 4096 https://qualcom-qpc-models.s3-accelerate.amazonaws.com/SDK1.20.2/openai/gpt-oss-120b/qpc_120b_ts4_cl4k_bs1_1spec_decode.tar.gz Download
MXFP6 8 16 1 1 4096 https://qualcom-qpc-models.s3-accelerate.amazonaws.com/SDK1.20.2/openai/gpt-oss-120b/qpc_120b_ts8_cl4k_bs1_1spec_decode.tar.gz Download
MXFP6 4 16 1 1 32768 https://qualcom-qpc-models.s3-accelerate.amazonaws.com/SDK1.20.2/openai/gpt-oss-120b/qpc_120b_ts4_cl32k_bs1_1spec_decode.tar.gz Download

Run This Model

# Download QPC
mkdir -p openai/gpt-oss-120b
cd openai/gpt-oss-120b
wget <Download URL>
tar xzvf <downloaded filename.tar.gz>

# Run QPC
python3 -m QEfficient.cloud.execute --model_name openai/gpt-oss-120b --qpc_path <path/to/qpc> --device_group [0,1,2,3] --prompt "# shortest path algorithm\n" --generation_len 128

API Endpoint

# Start REST endpoint with vLLM
VLLM_QAIC_MAX_CPU_THREADS=8 VLLM_QAIC_QPC_PATH=/path/to/qpc python3 -m vllm.entrypoints.openai.api_server \
  --host 0.0.0.0 \
  --port 8000 \
  --model openai/gpt-oss-120b \
  --max-model-len <Context Length> \
  --max-num-seq <Full Batch Size>  \
  --max-seq_len-to-capture <Chunking Prompt Length>  \
  --device qaic \
  --block-size 32