Update llama3.3_70b.py (#1739)

Summary
- Reduce number of samples as fairly hefty example

Author: dsikka

examples/big_models_with_sequential_onloading/llama3.3_70b.py

@@ -19,9 +19,9 @@
 DATASET_ID = "HuggingFaceH4/ultrachat_200k"
 DATASET_SPLIT = "train_sft"
 
-# Select number of samples. 512 samples is a good place to start.
+# Select number of samples.
 # Increasing the number of samples can improve accuracy.
-NUM_CALIBRATION_SAMPLES = 512
+NUM_CALIBRATION_SAMPLES = 256
 MAX_SEQUENCE_LENGTH = 2048
 
 # Load dataset and preprocess.