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debugging.md is becoming huge. We could either split it into multiple ones in a docs/debugging/ folder, or create a table of contents in the single file.
| - Simulates multi-GPU behavior on a single shared GPU | ||
| - Executes all collectives (all-reduce, all-gather, etc.) locally without network communication | ||
| - Maintains the same code paths as distributed training for accurate debugging | ||
| - Runs only one training step by default |
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why having this as default?
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Because under fake or local tensor modes, running more than one step doesn't give any more information. We cannot use either modes to verify memory usages or performance as it is not accurate. So one step should give users enough information.
docs/debugging.md
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| - Runs only one training step by default | ||
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| **When to use it:** | ||
| - Debugging distributed training logic (FSDP, TP, PP, CP, EP) with data dependencies without multi-GPU setup |
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add a note that fsdp doesn't work today?
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Stack from [ghstack](https://github.com/ezyang/ghstack/tree/0.12.0) (oldest at bottom): * __->__ pytorch#2162 As title
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Stack from ghstack (oldest at bottom):
As title