diff --git a/psi/algorithm/spiral/spiral_pir_test.cc b/psi/algorithm/spiral/spiral_pir_test.cc
index 4ff61ad..edf0a44 100644
--- a/psi/algorithm/spiral/spiral_pir_test.cc
+++ b/psi/algorithm/spiral/spiral_pir_test.cc
@@ -75,7 +75,7 @@ TEST_P(SpiralPirTest, Works) {
   SPDLOG_INFO("GenRandomDatabase, time cost: {} ms", timer.CountMs());
 
   // get a SpiralParams
-  auto spiral_params = util::GetPerformanceImproveParam();
+  auto spiral_params = util::GetDefaultParam();
   spiral_params.UpdateByDatabaseInfo(database_info);
 
   SPDLOG_INFO("MaxByteLenofPt: {}, MaxBitLenOfPt: {}",
@@ -173,4 +173,4 @@ INSTANTIATE_TEST_SUITE_P(Works_Instances, SpiralPirTest,
                                          TestParams{10000, 8193, true},
                                          TestParams{1000, 8192 * 10, true}));
 
-}  // namespace psi::spiral
\ No newline at end of file
+}  // namespace psi::spiral
diff --git a/psi/algorithm/spiral/util.cc b/psi/algorithm/spiral/util.cc
index a74bff6..49c590a 100644
--- a/psi/algorithm/spiral/util.cc
+++ b/psi/algorithm/spiral/util.cc
@@ -56,6 +56,19 @@ Params GetPerformanceImproveParam() {
                 std::move(poly_matrix_params), std::move(query_params));
 }
 
+Params GetDefaultParam() {
+  std::size_t poly_len{2048};
+  std::vector<std::uint64_t> moduli{268369921, 249561089};
+
+  double noise_width{6.4};
+
+  PolyMatrixParams poly_matrix_params(2, 256, 21, 4, 8, 8, 6);
+  QueryParams query_params(9, 6, 1);
+
+  return Params(poly_len, std::move(moduli), noise_width,
+                std::move(poly_matrix_params), std::move(query_params));
+}
+
 Params GetFastExpansionTestingParam() {
   std::size_t poly_len{2048};
   std::vector<std::uint64_t> moduli{268369921, 249561089};
diff --git a/psi/algorithm/spiral/util.h b/psi/algorithm/spiral/util.h
index 2213cd0..34583dc 100644
--- a/psi/algorithm/spiral/util.h
+++ b/psi/algorithm/spiral/util.h
@@ -25,8 +25,11 @@ Params GetFastExpansionTestingParam();
 
 Params GetTestParam();
 
+// this params has the best performance, but has smallest noise budget
 Params GetPerformanceImproveParam();
 
+Params GetDefaultParam();
+
 Params GetLargerParam();
 
 // calc multi-dimension position in 1-deimension's position