Commit Graph

7 Commits

Author SHA1 Message Date
Wing Lian
e4032fc90f Refactor separate attention flags with attn_implementation and capability/concerns feature flags (#3602)
* upgrade to torchao 0.17.0

* chore: lint

* refactor attention handling

* replace legacy attention boolean flags with capability properties

Replace checks with capability-based properties derived from attn_implementation

This separates three concerns that were conflated under flash_attention:
1. Backend selection -> attn_implementation enum
2. Packing capability -> attn_supports_packing property
3. Flash-attn library dependency -> attn_uses_flash_lib property

* compute attn capability flags in normalizer instead of properties

* make attn_implementation the single source of truth

* move attention-dependent validators to mode=after

* migrate remaining consumers to canonical attn_implementation

* expand attention tests + rewrite docs

* migrate example configs to canonical attn_implementation

* update doc snippets + reject gemma4-hybrid with non-FA2 backend

* remove dead gemma4 branch in _set_attention_config

* fix duplicate attn_implementation in gpt-oss yamls and flaky caplog tests

* drop "Phase 2" naming from attn-implementation tests

* regroup attn_implementation tests by feature concern

* clean up verbose comments and remove MD

Signed-off-by: Wing Lian <wing@axolotl.ai>
Co-authored-by: Axolotl Swarm <no-reply@axolotl.ai>

* fix(collator): pass return_dict=True at apply_chat_template top level for transformers 5.x

In transformers 5.x, ProcessorMixin.apply_chat_template gained its own
`return_dict` parameter (defaulting to False).  When return_dict=False
and tokenize=True the method returns out["input_ids"] directly — a 2-D
tensor — rather than the full BatchFeature dict.

The old code placed `return_dict=True` inside processor_kwargs.  In
transformers 5.x those kwargs are forwarded to the underlying processor
call self(...) where _merge_kwargs silently ignores any key not present
in MllamaProcessorKwargs (emitting a warning).  The outer return_dict
therefore stayed False, apply_chat_template returned the raw input_ids
tensor, and the subsequent `batch["input_ids"]` attempted to index a
2-D tensor with the 9-character string "input_ids", producing:

  IndexError: too many indices for tensor of dimension 2

The fix is to pass return_dict=True as a top-level keyword argument to
apply_chat_template (where it is actually consumed) and remove it from
processor_kwargs (where it was silently dropped).  No version guard is
needed: transformers is pinned to ==5.5.4 in pyproject.toml.

Adds a unit-level regression test (tests/test_mm_chat_collator.py) that
mocks the processor to return a raw tensor when apply_chat_template is
called without top-level return_dict=True, verifying the four invariants:
process_rows returns a dict, input_ids is 2-D, labels is 2-D, and
apply_chat_template receives return_dict=True as a top-level kwarg.

Fixes: tests/e2e/test_llama_vision.py::TestLlamaVision::test_lora_llama_vision_multimodal_dataset
Fixes: tests/e2e/test_llama_vision.py::TestLlamaVision::test_lora_llama_vision_text_only_dataset
Signed-off-by: Wing Lian <wing@axolotl.ai>
Co-authored-by: Axolotl Swarm <no-reply@axolotl.ai>

* fix(collator): process_rows returns dict (BatchFeature) shape

Two related changes for the multimodal chat collator under transformers 5.x:

1. Wrap apply_chat_template result in dict(...) so process_rows returns
   a plain dict rather than a BatchFeature instance. BatchFeature is a
   Mapping but not a dict; downstream code that did
     batch["labels"] = self.processing_strategy.process_labels(batch["input_ids"])
   would index on a tensor when the result wasn't dict-shaped, raising
     IndexError: too many indices for tensor of dimension 2

2. Soften the regression test's contract from `dict` to `Mapping` so it
   exercises the actual semantic guarantee (key/value access) rather
   than the implementation detail (dict vs BatchFeature). Test guards
   against the original transformers 5.x breakage where apply_chat_template's
   return_dict default went from True to False.

Includes regression test under tests/test_mm_chat_collator.py.

Bug surfaced via swarm dispatch task_01KQHPNAYD8XARSNSDJVW1GPF6 against
attn-implementation-refactor; squash-merged from agent commits 4de886fd
+ dc9fcf4f.

Signed-off-by: Wing Lian <wing@axolotl.ai>

---------

Signed-off-by: Wing Lian <wing@axolotl.ai>
Co-authored-by: Axolotl Swarm <no-reply@axolotl.ai>
2026-05-05 10:15:18 -04:00
salman
294c7fe7a6 Distributed/ND-Parallel (#2977) 2025-07-31 15:25:02 -04:00
Dan Saunders
6aa41740df SP dataloader patching + removing custom sampler / dataloader logic (#2686)
* utilize accelerate prepare_data_loader with patching

* lint

* cleanup, fix

* update to support DPO quirk

* small change

* coderabbit commits, cleanup, remove dead code

* quarto fix

* patch fix

* review comments

* moving monkeypatch up one level

* fix
2025-05-21 11:20:20 -04:00
Dan Saunders
80304c26a7 SP GRPO support + batch SP fixes (#2643)
* ctx manager for SP

* updates

* update

* further simplifying

* simplifying

* simplifying

* reorg

* batch api HF adapter for ring-flash-attn; cleanup and improvements

* update

* adding all batch ring-flash-attn methods via single adapter

* fix

* fixes for batch API funcs, simplify

* fix

* grpo sp support

* progress

* stronger subclassing of TRL GRPO trainer; custom distributed sampler

* subclassing constructor

* progress

* finalizing SP + GRPO trainer

* minimize diffs to GRPO trainer

* remove (most of) the custom GRPO trainer logic

* debug

* debug

* update

* update

* update

* progress

* cleanup

* cleanup

* minor changes

* update

* update

* update

* small changes

* updates

* cleanup; torch.compile ring_flash_attn functions to prevent numerical instability; lint

* spacing

* cleanup; log in pydantic model config only on main process

* remove comment

* fix sp sampler, update to latest upstream code, doc

* add docs

* update quartodoc autodoc contents

* fix, simplifications

* fixes + simplifications

* review comments

* lint

* removing main process only logs in favor of #2608

* fixes, additional smoke test

* updatse

* more tests

* update

* fix grad accum bug (sort of)

* lint, tests

* todo
2025-05-12 17:52:40 -04:00
Dan Saunders
b8c633aa97 batch api HF adapter for ring-flash-attn; cleanup and improvements (#2520)
* batch api HF adapter for ring-flash-attn; cleanup and improvements

* update

* adding all batch ring-flash-attn methods via single adapter

* removing pad_to_sequence_len=False for now

* fix

* updating docs to include batch SP

* review comments

* fixes for batch API funcs, simplify

* fixes

* fix

* updates

* add batch_zigzag smoke test
2025-04-16 13:50:48 -04:00
Dan Saunders
5410195e0b Sequence parallelism quick follow-ups; remove ModelCallback (#2450)
* guard return if ring attn alrady registered

* add docs link, bits in multi-gpu docs, remove save model callback (subsumed by HF trainers)

* configurable heads_k_stride from ring-flash-attn hf adapter
2025-03-31 09:13:42 -04:00
Dan Saunders
23f0c51d88 Sequence parallelism (#2412)
* adding easy_context as integration for now

* progress on ring attn impl

* progress on ring attn impl

* cleanup

* remove errant file

* fix req

* removing unused code

* updates

* pytest

* update

* updates

* fixes

* precommit fixes

* working multi-group SP

* fixing sample packing

* remove debug logs and simplify

* eval dataloader and sampler changes

* removing some obvious comments

* update config.qmd and rename option

* scoping down problematic import

* another import scoping change

* pernicious Fire CLI bugfix

* isolate cli tests

* actually isolate CLI tests

* gracefully handle no ring-flash-attn

* fix

* fix

* move ring flash attn to extras with flash-attn (#2414)

* removing flash-attn from requirements.txt (in setup.py extras already)

* rename file, delete another

* using field validator instead of model validator

* test fix

* sampler / dataloader refactor

* non-seq2se1 collator fix

* removing print statement

* bugfix

* add SP doc, review comments

* small changes

* review comments, docstrings

* refactors, SP mixin

* small updates

* fix tests

* precommit

* precommit

---------

Co-authored-by: Wing Lian <wing.lian@gmail.com>
Co-authored-by: Dan Saunders <dan@axolotl.ai>
2025-03-21 12:43:55 -04:00