diff --git a/setup.py b/setup.py
index e615a99e38bec85bab9bedfc7ab68b032e785655..e774a6c648c32f26226d9eb01b1ba96a8e2758a1 100644
--- a/setup.py
+++ b/setup.py
@@ -27,7 +27,7 @@ if __name__ == "__main__":
               CUDAExtension(module_name,
                             [generated_file] + cuda_sources,
                             extra_compile_args={'cxx': [],
-                                                'nvcc': ['-arch=sm_35']})
+                                                'nvcc': ['-arch=sm_35', '-O3']})
           ],
           cmdclass={
               'build_ext': BuildExtension