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--- |
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license: apache-2.0 |
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language: |
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- en |
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datasets: |
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- tiiuae/falcon-refinedweb |
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- bigcode/starcoderdata |
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- open-web-math/open-web-math |
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--- |
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## Introducation |
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Sparse computing is increasingly recognized as an important direction to improve the computational efficiency (e.g., inference speed) of large language models (LLM). |
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Recent studies ([Zhang el al., 2021](https://arxiv.org/abs/2110.01786); [Liu et al., 2023](https://openreview.net/pdf?id=wIPIhHd00i); [Mirzadeh et al., 2023](https://arxiv.org/abs/2310.04564)) reveal that LLMs inherently exhibit properties conducive to sparse computation when employing the ReLU activation function. |
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This insight opens up new avenues for inference speed, akin to MoE's selective activation. |
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By dynamically choosing model parameters for computation, we can substantially boost inference speed. |
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However, the widespread adoption of ReLU-based models in the LLM field remains limited. |
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Here we introduce a new 7B ReLU-based LLM, Bamboo (Github link: [https://github.com/SJTU-IPADS/Bamboo](https://github.com/SJTU-IPADS/Bamboo)), |
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which boasts nearly 85% sparsity and performance levels on par with [Mistral-7B](https://huggingface.co/mistralai/Mistral-7B-v0.1). |
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## Model Architecture |
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To push the model's sparsity, we add a ReLU component after GLU component, called dReLU(double ReLU). So our FFN network works as follows: |
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```Python |
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class BambooMLP(nn.Module): |
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def __init__(self, config): |
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super().__init__() |
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self.config = config |
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self.hidden_size = config.hidden_size |
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self.intermediate_size = config.intermediate_size |
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self.gate_proj = nn.Linear(self.hidden_size, self.intermediate_size, bias=False) |
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self.up_proj = nn.Linear(self.hidden_size, self.intermediate_size, bias=False) |
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self.down_proj = nn.Linear(self.intermediate_size, self.hidden_size, bias=False) |
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self.act_fn = ACT2FN[config.hidden_act] |
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def forward(self, x): |
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return self.down_proj(self.act_fn(self.gate_proj(x)) * self.act_fn(self.up_proj(x))) |
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``` |
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## Training Details |
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In this section, we introduce the details of training our model, including types of data used, and hyperparameters. |
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We initialized the model weights to Mistral's model weights and modified the FFN structure to the dReLU structure, then continued pre-training for 200B tokens, divided into two phases: |
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**First phase**: For the proportion of training corpus, we followed the data mix ratio and sources of the StableLM-3B model ([link](https://stability.wandb.io/stability-llm/stable-lm/reports/StableLM-3B-4E1T--VmlldzoyMjU4?accessToken=u3zujipenkx5g7rtcj9qojjgxpconyjktjkli2po09nffrffdhhchq045vp0wyfo)), conducting a further pre-training with 150B tokens. |
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The following table shows the hyper-paramters we used in our training process. |
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| Hyper-parameters | | |
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| --------------------- | ----------- | |
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| GPUs | 64 80G-A800 | |
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| Learning Rate Control | Cosine | |
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| Peak Learning Rate | 5e-5 | |
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| Batch Size | 4M | |
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| Weight Decay | 0.1 | |
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| Context Length | 2k | |
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**Second phase**: We further adjusted the training corpus ratio, incorporating more domain-specific datasets (e.g., Math, Coding), and continued training for 50B tokens. |
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| Hyper-parameters | | |
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| --------------------- | ----------- | |
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| GPUs | 64 80G-A800 | |
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| Learning Rate Control | Cosine | |
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| Peak Learning Rate | 5e-6 | |
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| Batch Size | 4M | |
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| Weight Decay | 0.01 | |
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| Context Length | 4k | |
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## Performance Evaluation Results |
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Our evaluation is based on the framework lm-evaluation-harness and opencompass. The evaluation details are listed as follows: |
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- Huggingface LLM Leaderboard tasks. |
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- Other Popular Benchmarks: We report the average accuracies on Big Bench Hard (BBH) (3-shot), HumanEval. |
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| | Average | MMLU | Winogrande | TruthfulQA | Hellaswag | GSM8K | Arc-C | HumanEval | BBH | |
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| ------- | ------ | ---------- | ---------- | --------- | ------ | ------ | --------- | ---- | ------- | |
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| Bamboo | **57.1** | 63.89 | 76.16 | 44.06 | 82.17 | 52.84 | 62.20 | 25.6 | 50.35 | |
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| Mistral-v0.1 | **56.5** | 62.65 | 79.24 | 42.62 | 83.32 | 40.18 | 61.43 | 26.21 | 56.35 | |
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## Inference Speed Evaluation Results |
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We utilize [PowerInfer](https://github.com/SJTU-IPADS/PowerInfer), a state-of-the-art acceleration framework leveraging activation sparsity. |
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Here we show the inference speed compared with llama.cpp/transformers. |
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## Limitation & Disclaimer |
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- Bamboo, having undergone training with only 200B tokens, may still exhibit performance gaps in certain tasks. |
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- The Bamboo model has only been trained on English-language datasets, hence its capabilities in other languages are still lacking. |
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- The model may produce unexpected outputs due to its size and probabilistic generation paradigm. |
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## License |
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The code is licensed under Apache-2.0, while model weights are fully open for academic research and also allow **free** commercial usage. |
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## Citation |
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Please kindly cite using the following BibTeX: |
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``` |
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@misc{bamboo, |
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title={Bamboo: Harmonizing Sparsity and Performance in Large Language Models}, |
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author={Yixin Song, Haotong Xie, Zeyu Mi, Li Ma, Haibo Chen}, |
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year={2024} |
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} |
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``` |
