deepspeedai / deepspeedai/DeepSpeed
[BUG] apply_tensor_parallelism() is not executed in Zero3 without self.mpu
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Description
Describe the bug
In Hybrid Engine, the apply_tensor_parallelism() is not called when model inference container requires tp > 1 but self.mpu is None. For example, for a large model in Zero3, the apply_tensor_parallelism() is not called.
Log output
To reproduce - call any large model, say Llama 30b using Zero 3 + Hybrid Engine.
Contributor guide
First steps
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Research direction
Start at deepspeed/runtime/hybrid_engine.py around line 206 and trace the conditions that control apply_tensor_parallelism(). Reproduce with a large model such as Llama 30b using Zero3 and Hybrid Engine, then verify that tensor parallelism is applied when inference requires tp > 1 and self.mpu is None.
Written by the indexing model from the issue text.
Assessment
- Tech stack
- python
- Domain
- distributed-systems, machine-learning
- Issue type
- Bug
- Difficulty
- 4/5
- Estimated time
- 3-5 days
- Activity status
- Stale
- Clarity
- Mostly clear
- Newbie friendliness
- 35/100