Instructions to use google/gemma-2-9b-it with libraries, inference providers, notebooks, and local apps. Follow these links to get started.
- Libraries
- Transformers
How to use google/gemma-2-9b-it with Transformers:
# Use a pipeline as a high-level helper from transformers import pipeline pipe = pipeline("text-generation", model="google/gemma-2-9b-it") messages = [ {"role": "user", "content": "Who are you?"}, ] pipe(messages)# Load model directly from transformers import AutoTokenizer, AutoModelForCausalLM tokenizer = AutoTokenizer.from_pretrained("google/gemma-2-9b-it") model = AutoModelForCausalLM.from_pretrained("google/gemma-2-9b-it") messages = [ {"role": "user", "content": "Who are you?"}, ] inputs = tokenizer.apply_chat_template( messages, add_generation_prompt=True, tokenize=True, return_dict=True, return_tensors="pt", ).to(model.device) outputs = model.generate(**inputs, max_new_tokens=40) print(tokenizer.decode(outputs[0][inputs["input_ids"].shape[-1]:])) - Inference
- Local Apps Settings
- vLLM
How to use google/gemma-2-9b-it with vLLM:
Install from pip and serve model
# Install vLLM from pip: pip install vllm # Start the vLLM server: vllm serve "google/gemma-2-9b-it" # Call the server using curl (OpenAI-compatible API): curl -X POST "http://localhost:8000/v1/chat/completions" \ -H "Content-Type: application/json" \ --data '{ "model": "google/gemma-2-9b-it", "messages": [ { "role": "user", "content": "What is the capital of France?" } ] }'Use Docker
docker model run hf.co/google/gemma-2-9b-it
- SGLang
How to use google/gemma-2-9b-it with SGLang:
Install from pip and serve model
# Install SGLang from pip: pip install sglang # Start the SGLang server: python3 -m sglang.launch_server \ --model-path "google/gemma-2-9b-it" \ --host 0.0.0.0 \ --port 30000 # Call the server using curl (OpenAI-compatible API): curl -X POST "http://localhost:30000/v1/chat/completions" \ -H "Content-Type: application/json" \ --data '{ "model": "google/gemma-2-9b-it", "messages": [ { "role": "user", "content": "What is the capital of France?" } ] }'Use Docker images
docker run --gpus all \ --shm-size 32g \ -p 30000:30000 \ -v ~/.cache/huggingface:/root/.cache/huggingface \ --env "HF_TOKEN=<secret>" \ --ipc=host \ lmsysorg/sglang:latest \ python3 -m sglang.launch_server \ --model-path "google/gemma-2-9b-it" \ --host 0.0.0.0 \ --port 30000 # Call the server using curl (OpenAI-compatible API): curl -X POST "http://localhost:30000/v1/chat/completions" \ -H "Content-Type: application/json" \ --data '{ "model": "google/gemma-2-9b-it", "messages": [ { "role": "user", "content": "What is the capital of France?" } ] }' - Docker Model Runner
How to use google/gemma-2-9b-it with Docker Model Runner:
docker model run hf.co/google/gemma-2-9b-it
Question about lm_head weights in Gemma-2-9b-it model
I've noticed some inconsistencies regarding the lm_head component in the google/gemma-2-9b-it model:
The model.safetensors.index.json file does not contain an lm_head.

When I load the model directly and save it using model.save_pretrained(), the resulting safetensors file also lacks an lm_head.
However, when I print the model structure, the lm_head is present, and the inference results are good.
Gemma2ForCausalLM(
(model): Gemma2Model(
(embed_tokens): Embedding(256000, 3584, padding_idx=0)
(layers): ModuleList(
(0-41): 42 x Gemma2DecoderLayer(
(self_attn): Gemma2SdpaAttention(
(q_proj): Linear(in_features=3584, out_features=4096, bias=False)
(k_proj): Linear(in_features=3584, out_features=2048, bias=False)
(v_proj): Linear(in_features=3584, out_features=2048, bias=False)
(o_proj): Linear(in_features=4096, out_features=3584, bias=False)
(rotary_emb): Gemma2RotaryEmbedding()
)
(mlp): Gemma2MLP(
(gate_proj): Linear(in_features=3584, out_features=14336, bias=False)
(up_proj): Linear(in_features=3584, out_features=14336, bias=False)
(down_proj): Linear(in_features=14336, out_features=3584, bias=False)
(act_fn): PytorchGELUTanh()
)
(input_layernorm): Gemma2RMSNorm()
(post_attention_layernorm): Gemma2RMSNorm()
(pre_feedforward_layernorm): Gemma2RMSNorm()
(post_feedforward_layernorm): Gemma2RMSNorm()
)
)
(norm): Gemma2RMSNorm()
)
(lm_head): Linear(in_features=3584, out_features=256000, bias=False)
)
This suggests that the lm_head might not be using initial values. I'm curious about the source of the lm_head weights in this case.
Questions:
- Where are the lm_head weights coming from?
- Why don't they appear in the safetensors files?
- Is this behavior intended?
Any clarification on this matter would be greatly appreciated. Thank you!
@mjkmain The default tie_word_embeddings of Gemma2Config (defined in transformers/models/gemma2/configuration_gemma2.py) is True, so the output embeddings are tied with the input ones, meaning that they are the same. You can refer to https://paperswithcode.com/method/weight-tying for more on weighting tying.
