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docs/features/quantization/inc.md

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+# FP8 INC
+
+vLLM supports FP8 (8-bit floating point) weight and activation quantization using Intel® Neural Compressor (INC) on Intel® Gaudi® 2 and Intel® Gaudi® 3 AI accelerators.
+Currently, quantization is validated only in Llama models.
+
+Intel Gaudi supports quantization of various modules and functions, including, but not limited to `Linear`, `KVCache`, `Matmul` and `Softmax`. For more information, please refer to:
+[Supported Modules\\Supported Functions\\Custom Patched Modules](https://docs.habana.ai/en/latest/PyTorch/Inference_on_PyTorch/Quantization/Inference_Using_FP8.html#supported-modules).
+
+!!! note
+    Measurement files are required to run quantized models with vLLM on Gaudi accelerators. The FP8 model calibration procedure is described in the [vLLM HPU extension](https://github.com/HabanaAI/vllm-hpu-extension/tree/main/calibration/README.md) package.
+
+!!! note
+    `QUANT_CONFIG` is an environment variable that points to the measurement or quantization [JSON config file](https://docs.habana.ai/en/latest/PyTorch/Inference_on_PyTorch/Quantization/Inference_Using_FP8.html#supported-json-config-file-options).
+    The measurement configuration file is used during the calibration procedure to collect measurements for a given model. The quantization configuration is used during inference.
+
+## Run Online Inference Using FP8
+
+Once you've completed the model calibration process and collected the measurements, you can run FP8 inference with vLLM using the following command:
+
+```bash
+export QUANT_CONFIG=/path/to/quant/config/inc/meta-llama-3.1-405b-instruct/maxabs_measure_g3.json
+vllm serve meta-llama/Llama-3.1-405B-Instruct --quantization inc --kv-cache-dtype fp8_inc --tensor_paralel_size 8
+```
+
+!!! tip
+    When using FP8 models, you may experience timeouts caused by the long compilation time of FP8 operations. To mitigate this problem, you can use the below environment variables:
+    `VLLM_ENGINE_ITERATION_TIMEOUT_S` - to adjust the vLLM server timeout. You can set the value in seconds, e.g., 600 equals 10 minutes.
+    `VLLM_RPC_TIMEOUT` - to adjust the RPC protocol timeout used by the OpenAI-compatible API. This value is in microseconds, e.g., 600000 equals 10 minutes.
+
+## Run Offline Inference Using FP8
+
+To run offline inference (after completing the model calibration process):
+
+* Set the "QUANT_CONFIG" environment variable to point to a JSON configuration file with QUANTIZE mode.
+* Pass `quantization=inc` and `kv_cache_dtype=fp8_inc` as parameters to the `LLM` object.
+* Call shutdown method of the model_executor at the end of the run.
+
+```python
+from vllm import LLM
+llm = LLM("llama3.1/Meta-Llama-3.1-8B-Instruct", quantization="inc", kv_cache_dtype="fp8_inc")
+...
+# Call llm.generate on the required prompts and sampling params.
+...
+llm.llm_engine.model_executor.shutdown()
+```
+
+## Device for the Model's Weights Uploading
+
+The unquantized weights are first loaded onto the CPU, then quantized and transferred to the target device (HPU) for model execution.
+This reduces the device memory footprint of model weights, as only quantized weights are stored in the device memory.