pytorch / pytorch/torchtitan

Pipeline Parallelism + FSDP

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#562 7 comments 0 reactions 1 assignee View on GitHub

@H-Huang is already working on this.

Since Oct 27, 2025.

enhancement module: pipelining question
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Description

On PP + FSDP and PP + TP + FSDP:

  • Is there any documentation on how these different parallelisms compose?
  • What are the largest training runs these strategies have been tested on?
  • Are there benchmarks for how these strategies compare against other distributed training frameworks that expose similar parallelisms?

Particularly interested in how PP + FSDP work together as it seems DeepSpeed explicitly disallows ZeRO 2/3 + PP (see here specifically, and here for discussion).

@wconstab @weifengpy @wanchaol

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