[BUG] 额外添加20个样本,防止制作预训练数据的时候超过index (#8789)

paddlenlp/data/causal_dataset.py

@@ -94,10 +94,11 @@ def get_datasets_weights_and_num_samples(data_prefix, train_val_test_num_samples
     # Add 0.5% (the 1.005 factor) so in case the bleding dataset does
     # not uniformly distribute the number of samples, we still have
     # samples left to feed to the network.
+    # (NOTE, yujun06): This is a workaround to avoid issues with indexing in the blending dataset. Therefore, we need to add 20 samples to each dataset.
     datasets_train_valid_test_num_samples = []
     for weight in weights:
         datasets_train_valid_test_num_samples.append(
-            [int(math.ceil(val * weight * 1.005)) for val in train_val_test_num_samples]
+            [int(math.ceil(val * weight * 1.005)) + 20 for val in train_val_test_num_samples]
         )
 
     return prefixes, weights, datasets_train_valid_test_num_samples