DeepSpec

DeepSpec is a full-stack codebase for training and evaluating draft models for speculative decoding. It contains data preparation utilities, draft model implementations, training code, and evaluation scripts.

Environment

Install the Python dependencies:

python -m pip install -r requirements.txt

Data preparation additionally requires an inference engine to serve the target model when regenerating answers; see scripts/data/README.md for details.

Workflow

Run the stages in order — each stage's output feeds the next:

1. Data Preparation — download prompts, regenerate target answers, and build the target cache.
2. Training — train a draft model against the cached target outputs.
3. Evaluation — measure speculative-decoding acceptance on benchmark tasks.

Data Preparation

See scripts/data/README.md for the step-by-step data pipeline:

1. download and split training data,
2. regenerate answers,
3. prepare the target cache (storage warning: this can be very large — roughly 38 TB for the default Qwen/Qwen3-4B setting).

Training

bash scripts/train/train.sh

train.sh launches train.py, which spawns one worker per visible GPU. Select the algorithm and target model by pointing config_path at one of the configs under config/ (e.g. config/dspark/dspark_qwen3_4b.py); see the script header for the full list of configs, how to override config_path / target_cache_dir, and how to use --opts to override individual config fields. Checkpoints are written to ~/checkpoints///step_*.

Hardware: the default configs and scripts assume a single node with 8 GPUs. For fewer GPUs, reduce CUDA_VISIBLE_DEVICES.

Evaluation

bash scripts/eval/eval.sh

eval.sh runs eval.py against a trained draft checkpoint over the speculative-decoding benchmarks in eval_datasets/ (gsm8k, math500, aime25, humaneval, mbpp, livecodebench, mt-bench, alpaca, arena-hard-v2). Set:

• target_name_or_path — the target model the draft was trained against (e.g. Qwen/Qwen3-4B),
• draft_name_or_path — the draft checkpoint, e.g. ~/checkpoints/deepspec/dspark_block7_qwen3_4b/step_latest, or one of the Hugging Face repo IDs listed in Released Checkpoints.

Released Checkpoints

The checkpoint