diff --git a/Makefile b/Makefile
index e1d361f..4d410e0 100644
--- a/Makefile
+++ b/Makefile
@@ -2,7 +2,7 @@ all: install data train eval
 
 city_distances_full.csv: check generate_data.py
 	@echo "Generating distance data..."
-	@bash -c 'time python generate_data.py --country US --workers 8 --chunk-size 8000'
+	@bash -c 'time python generate_data.py --country US --workers 8 --chunk-size 4200'
 
 data: city_distances_full.csv
 
diff --git a/generate_data.py b/generate_data.py
index 2fdb3da..d255a8e 100644
--- a/generate_data.py
+++ b/generate_data.py
@@ -34,6 +34,11 @@ parser.add_argument(
     type=str,
     default="city_distances_full.csv",
 )
+parser.add_argument(
+    "--shuffle",
+    action="store_true",
+    help="Option to shuffle combinations list before iterating over it",
+)
 args = parser.parse_args()
 
 
@@ -116,7 +121,8 @@ def main():
     cities = list(us_cities.values())
     print(f"Num cities: {len(cities)}")
     city_combinations = list(itertools.combinations(cities, 2))
-    # np.random.shuffle(city_combinations)  # will this help or hurt caching? 1.03it/s
+    if args.shuffle:
+        np.random.shuffle(city_combinations)
     chunk_size = args.chunk_size
     num_chunks = len(city_combinations) // chunk_size + 1
     output_file = args.output_file