fix pretraining_ on odd datasets (#1463)

* can configure name of split of pretraining dataset

* streaming data and dataset map

* text column customized

* allow text_column to be set in pretrain

* pretrain type

* load a bit of the dataset

* fix dataset where splits have separate configs

* ok name param here is the config

* whitespace

src/axolotl/prompt_strategies/pretrain.py

@@ -20,10 +20,11 @@ class PretrainTokenizationStrategy(PromptTokenizingStrategy):
     def supports_batched(self):
         return True
 
-    def __init__(self, *args, max_length=None, **kwargs):
+    def __init__(self, *args, max_length=None, text_column="text", **kwargs):
         super().__init__(*args, **kwargs)
         if max_length:
             self.max_length = max_length
+        self.text_column = text_column
 
     def _tokenize(
         self, prompt: str, add_eos_token: bool = True, strip_bos_token: bool = False
@@ -44,7 +45,7 @@ def _tokenize(
         return res
 
     def tokenize_prompt(self, prompt):
-        return self._tokenize(prompt["text"])
+        return self._tokenize(prompt[self.text_column])
 
 
 def load(tokenizer, cfg):
@@ -53,6 +54,7 @@ def load(tokenizer, cfg):
         tokenizer,
         cfg.train_on_inputs,
         cfg.sequence_len,
+        text_column=cfg.pretraining_dataset[0]["text_column"] or "text",
         max_length=cfg.sequence_len * 64,
     )
     return strat

src/axolotl/utils/config/models/input/v0_4_1/__init__.py

@@ -61,7 +61,11 @@ class RemappedParameters(BaseModel):
 class PretrainingDataset(BaseModel):
     """pretraining dataset configuration subset"""
 
+    name: Optional[str] = None
     path: Optional[str] = None
+    split: Optional[str] = "train"
+    text_column: Optional[str] = "text"
+    type: Optional[str] = "pretrain"
 
 
 class UserDefinedPrompterType(BaseModel):
@@ -448,7 +452,7 @@ class Config:
     dataset_shard_idx: Optional[int] = None
 
     pretraining_dataset: Optional[  # type: ignore
-        conlist(Union[SFTDataset, PretrainingDataset], min_length=1)
+        conlist(Union[PretrainingDataset, SFTDataset], min_length=1)
     ] = Field(
         default=None, metadata={"help": {"streaming dataset to use for pretraining"}}
     )

src/axolotl/utils/data.py

@@ -82,12 +82,15 @@ def prepare_dataset(cfg, tokenizer):
                 )
     else:
         path = cfg.pretraining_dataset
+        split = "train"
         name = None
         if isinstance(cfg.pretraining_dataset, list) and isinstance(
             cfg.pretraining_dataset[0], dict
         ):
             path = cfg.pretraining_dataset[0]["path"]
             name = cfg.pretraining_dataset[0]["name"]
+            if "split" in cfg.pretraining_dataset[0]:
+                split = cfg.pretraining_dataset[0]["split"]
 
         ds_wrapper_partial = functools.partial(
             get_dataset_wrapper,
@@ -98,7 +101,7 @@ def prepare_dataset(cfg, tokenizer):
         )
 
         train_dataset = wrap_pretraining_dataset(
-            load_dataset(path, streaming=True, split="train", name=name),
+            load_dataset(path, streaming=True, split=split, name=name),
             tokenizer,
             cfg,
             ds_wrapper_partial,
@@ -831,14 +834,23 @@ def wrap_pretraining_dataset(
     else:
         LOG.debug("NOT shuffling merged pretraining datasets")
 
+    # remove all the existing columns after mapping since they end up having
+    # a different length than the encoded/tokenized column
+    # this is empty during streaming/pretraining
+    remove_columns = []
+    if dataset.features is None:
+        for first_row in dataset:
+            remove_columns = first_row.keys()
+            break
+    else:
+        remove_columns = dataset.features.keys()
+
     dataset = dataset.map(
         encode,
         batched=True,
         batch_size=buffer_size,
         # input_columns="text",
-        # remove all the existing columns after mapping since they end up having
-        # a different length than the encoded/tokenized column
-        remove_columns=dataset.features.keys(),
+        remove_columns=remove_columns,
     )
     return dataset