Pipefusion sd3

[XinzeLi]

用crossing中的通信包postal service与parallel context实现了pipefusion

主要做了以下修改:

• cache manager进行kv cache的管理.
• 根据pipeline处在的stage, 内部修改了transformer的流程.
• 对于每个attention block需要用到的patch embedding和conv2d都根据patch的方式做了修改.
• pipeline本身当然也要进行修改, 支持cfg 并行.
• 现在暂时借鉴xdit实现了group coordinator, runtime state, 后续假如需要可以用crossing中的parallel context来改写.
• 使用run.sh来传参给sd3_example.py来跑pipeline, 并行的参数可以在里面修改

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