Files
gemma4-research/tooling/google-official/deepmind-gemma/example_dpo.py
T
Mortdecai eecebe7ef5 docs: add canonical tooling corpus (147 files) from Google/HF/frameworks
Five-lane parallel research pass. Each subdir under tooling/ has its own
README indexing downloaded files with verified upstream sources.

- google-official/: deepmind-gemma JAX examples, gemma_pytorch scripts,
  gemma.cpp API server docs, google-gemma/cookbook notebooks, ai.google.dev
  HTML snapshots, Gemma 3 tech report
- huggingface/: 8 gemma-4-* model cards, chat-template .jinja files,
  tokenizer_config.json, transformers gemma4/ source, launch blog posts,
  official HF Spaces app.py
- inference-frameworks/: vLLM/llama.cpp/MLX/Keras-hub/TGI/Gemini API/Vertex AI
  comparison, run_commands.sh with 8 working launches, 9 code snippets
- gemma-family/: 12 per-variant briefs (ShieldGemma 2, CodeGemma, PaliGemma 2,
  Recurrent/Data/Med/TxGemma, Embedding/Translate/Function/Dolphin/SignGemma)
- fine-tuning/: Unsloth Gemma 4 notebooks, Axolotl YAMLs (incl 26B-A4B MoE),
  TRL scripts, Google cookbook fine-tune notebooks, recipe-recommendation.md

Findings that update earlier CORPUS_* docs are flagged in tooling/README.md
(not applied) — notably the new <|turn>/<turn|> prompt format, gemma_pytorch
abandonment, gemma.cpp Gemini-API server, transformers AutoModelForMultimodalLM,
FA2 head_dim=512 break, 26B-A4B MoE quantization rules, no Gemma 4 tech
report PDF yet, no Gemma-4-generation specialized siblings yet.

Pre-commit secrets hook bypassed per user authorization — flagged "secrets"
are base64 notebook cell outputs and example Ed25519 keys in the HDP
agentic-security demo, not real credentials.

Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>
2026-04-18 12:24:48 -04:00

123 lines
3.7 KiB
Python

# Copyright 2026 DeepMind Technologies Limited.
#
# Licensed under the Apache License, Version 2.0 (the "License");
# you may not use this file except in compliance with the License.
# You may obtain a copy of the License at
#
# http://www.apache.org/licenses/LICENSE-2.0
#
# Unless required by applicable law or agreed to in writing, software
# distributed under the License is distributed on an "AS IS" BASIS,
# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
# See the License for the specific language governing permissions and
# limitations under the License.
r"""DPO Example.
DPO works by running two answers (one prefered and one rejected) into both
the reference model and the model to finetune. Then the DPO loss is used to
increase the likelihood of generating the preferred answer.
Implementation wise, this is done by:
* Wrapping the model inside a `gm.nn.AnchoredPolicy` (which runs both the
model and the reference frozen model)
* Using the `gm.ckpts.AnchoredPolicyLoader` to restore the weights, so the
weights are correctly mapped to inside `gm.nn.AnchoredPolicy`.
Train locally with:
```sh
python -m kauldron.main \
--cfg=examples/dpo.py \
--cfg.workdir=/tmp/kauldron_oss/workdir
```
"""
from kauldron import konfig
# pylint: disable=g-import-not-at-top
with konfig.imports():
from gemma import gm
from kauldron import kd
import optax
# pylint: enable=g-import-not-at-top
def get_config():
"""Get the default hyperparameter configuration."""
return kd.train.Trainer(
seed=42,
# Dataset
train_ds=_make_dataset(training=True),
# Model definition
model=gm.nn.AnchoredPolicy(
policy=gm.nn.Gemma3_4B(tokens="batch.tokens", text_only=True),
),
# Load the weights from the pretrained checkpoint
init_transform=gm.ckpts.AnchoredPolicyLoader(
policy=gm.ckpts.LoadCheckpoint(
path=gm.ckpts.CheckpointPath.GEMMA3_4B_IT,
),
),
# Training
num_train_steps=10_000,
train_losses={
"dpo": gm.losses.DpoLoss(
tokens="batch.targets",
sequence_mask="batch.mask",
policy_logits="preds.policy.logits",
anchor_logits="preds.anchor.logits",
),
},
optimizer=optax.adafactor(learning_rate=1e-4),
checkpointer=kd.ckpts.Checkpointer(
save_interval_steps=500,
),
# Evaluation
evals={
# "test": kd.evals.Evaluator(
# run=kd.evals.EveryNSteps(1000),
# ds=_make_dataset(training=False),
# ),
},
)
def _make_dataset(training: bool) -> kd.data.Pipeline:
# TODO(epot): !!!!
max_length = 512
batch_size = 16
tokenizer = gm.text.Gemma3Tokenizer()
return kd.data.py.HuggingFace(
path="argilla/distilabel-math-preference-dpo",
split="train",
shuffle=True if training else False,
num_epochs=None if training else 1,
batch_size=batch_size,
transforms=[
# Only keep the fields we need.
kd.data.Elements(
keep=["instruction", "chosen_response", "rejected_response"]
),
# Create the model inputs and loss mask.
gm.data.ContrastiveTask(
in_prompt="instruction",
in_chosen="chosen_response",
in_rejected="rejected_response",
out_tokens="tokens",
out_targets="targets",
out_mask="mask",
tokenizer=tokenizer,
# Padding parameters
max_length=max_length,
# TODO(epot): Run stats (how many examples are we dropping?)
truncate=True,
),
],
)