Skip to content

Add shuffle_dataset option to SFTTrainer #4564

New issue

Have a question about this project? Sign up for a free GitHub account to open an issue and contact its maintainers and the community.

Sign up for GitHub

By clicking “Sign up for GitHub”, you agree to our terms of service and privacy statement. We’ll occasionally send you account related emails.

Already on GitHub? Sign in to your account

Merged
qgallouedec merged 2 commits into from
Nov 25, 2025
Merged

Add shuffle_dataset option to SFTTrainer #4564

Show file tree
Hide file tree
Changes from all commits
Commits
Show all changes
2 commits
Select commit Hold shift + click to select a range
3b98bd2
feat: add shuffle_dataset option to SFTConfig and implement dataset s…
qgallouedec Nov 23, 2025
e8477a6
Merge branch 'main' into shuffle-dataset-sft
qgallouedec Nov 24, 2025
File filter

Filter by extension

Filter by extension
Conversations
Failed to load comments.
Loading
Jump to
Jump to file
Failed to load files.
Loading
Diff view
Diff view
6 changes: 6 additions & 0 deletions trl/trainer/sft_config.py
View file
Open in desktop
Original file line number Diff line number Diff line change
Expand Up @@ -64,6 +64,8 @@ class SFTConfig(TrainingArguments):
max_length (`int` or `None`, *optional*, defaults to `1024`):
Maximum length of the tokenized sequence. Sequences longer than `max_length` are truncated from the right.
If `None`, no truncation is applied. When packing is enabled, this value sets the sequence length.
shuffle_dataset (`bool`, *optional*, defaults to `False`):
Whether to shuffle the dataset.
packing (`bool`, *optional*, defaults to `False`):
Whether to group multiple sequences into fixed-length blocks to improve computational efficiency and reduce
padding. Uses `max_length` to define sequence length.
Expand Down Expand Up @@ -197,6 +199,10 @@ class SFTConfig(TrainingArguments):
"sequence length."
},
)
shuffle_dataset: bool = field(
default=False,
metadata={"help": "Whether to shuffle the dataset."},
)
packing: bool = field(
default=False,
metadata={
Expand Down
8 changes: 8 additions & 0 deletions trl/trainer/sft_trainer.py
View file
Open in desktop
Original file line number Diff line number Diff line change
Expand Up @@ -1071,6 +1071,11 @@ def tokenize_fn(example, processing_class, dataset_text_field, assistant_only_lo

dataset = dataset.select_columns(columns)

# Shuffle the dataset before packing. When using wrapped packing, it's important to shuffle before
# packing as well to avoid correlations between sequences packed together.
if args.shuffle_dataset:
dataset = dataset.shuffle(seed=args.seed)

# Packing adds new column "seq_lengths" needed for document aware FlashAttention
dataset = pack_dataset(dataset, args.max_length, args.packing_strategy, map_kwargs)
elif args.max_length is not None:
Expand All @@ -1083,6 +1088,9 @@ def tokenize_fn(example, processing_class, dataset_text_field, assistant_only_lo
column_names = get_dataset_column_names(dataset)
dataset = dataset.select_columns(collator_expected_keys.intersection(column_names))

if args.shuffle_dataset:
dataset = dataset.shuffle(seed=args.seed)

return dataset

def _set_signature_columns_if_needed(self):
Expand Down
Loading