perf: memory consumption for the Batch-Wise Balance History report

erpnext/stock/report/batch_wise_balance_history/batch_wise_balance_history.py

@@ -117,11 +117,14 @@ def get_stock_ledger_entries(filters):
 		if filters.get(field):
 			query = query.where(sle[field] == filters.get(field))
 
-	return query.run(as_dict=True)
+	return query
 
 
 def get_item_warehouse_batch_map(filters, float_precision):
+	with frappe.db.unbuffered_cursor():
 		sle = get_stock_ledger_entries(filters)
+		sle = sle.run(as_dict=True, as_iterator=True)
+
 		iwb_map = {}
 
 		from_date = getdate(filters["from_date"])