diff --git a/tests/benchmarks/CMakeLists.txt b/tests/benchmarks/CMakeLists.txt
index 31f13e17..483b0453 100644
--- a/tests/benchmarks/CMakeLists.txt
+++ b/tests/benchmarks/CMakeLists.txt
@@ -15,6 +15,7 @@
 add_executable(casbin_benchmark
     config_path.h
     main.cpp
+    model_b.cpp
     enforcer_cached_b.cpp
     management_api_b.cpp
     role_manager_b.cpp
diff --git a/tests/benchmarks/model_b.cpp b/tests/benchmarks/model_b.cpp
index ab9276fd..e603e8d9 100644
--- a/tests/benchmarks/model_b.cpp
+++ b/tests/benchmarks/model_b.cpp
@@ -39,7 +39,7 @@ BENCHMARK(BenchmarkRaw);
 
 static void BenchmarkBasicModel(benchmark::State& state) {
     casbin::Enforcer e(basic_model_path, basic_policy_path);
-    std::vector<std::string> params = {"alice", "data1", "read"};
+    casbin::DataList params = {"alice", "data1", "read"};
 
     for(auto _ : state)
         e.Enforce(params);
@@ -50,7 +50,7 @@ BENCHMARK(BenchmarkBasicModel);
 static void BenchmarkRBACModel(benchmark::State& state) {
     casbin::Enforcer e(rbac_model_path, rbac_policy_path);
 
-    std::vector<std::string> params = {"alice", "data2", "read"};
+    casbin::DataList params = {"alice", "data2", "read"};
 
     for (auto _ : state)
         e.Enforce(params);
@@ -60,17 +60,16 @@ BENCHMARK(BenchmarkRBACModel);
 
 static void BenchmarkRBACModelSmall(benchmark::State& state) {
     casbin::Enforcer e(rbac_model_path);
-    std::vector<std::string> params(3);
 
     // 100 roles, 10 resources.
     for(int i = 0; i < 100; ++i)
-        params = { "group" + std::to_string(i), "data" + std::to_string(i/10), "read" }, e.AddPolicy(params);
+        e.AddPolicy({ "group" + std::to_string(i), "data" + std::to_string(i/10), "read" });
 
     // 1000 users.
     for(int i = 0; i < 1000; ++i)
-        params = { "user" + std::to_string(i), "group" + std::to_string(i / 10) }, e.AddGroupingPolicy(params);
+        e.AddGroupingPolicy({ "user" + std::to_string(i), "group" + std::to_string(i / 10) });
 
-    params = {"user501", "data9", "read"};
+    casbin::DataList params = {"user501", "data9", "read"};
     for (auto _ : state)
         e.Enforce(params);
 }
@@ -79,17 +78,16 @@ BENCHMARK(BenchmarkRBACModelSmall);
 
 static void BenchmarkRBACModelMedium(benchmark::State& state) {
     casbin::Enforcer e(rbac_model_path);
-    std::vector<std::string> params(3);
 
     // 1000 roles, 100 resources.
     for (int i = 0; i < 1000; ++i)
-        params = {"group" + std::to_string(i), "data" + std::to_string(i / 10), "read"}, e.AddPolicy(params);
+        e.AddPolicy({"group" + std::to_string(i), "data" + std::to_string(i / 10), "read"});
 
     // 10000 users.
     for (int i = 0; i < 10000; ++i)
-        params = {"user" + std::to_string(i), "group" + std::to_string(i / 10)}, e.AddGroupingPolicy(params);
+        e.AddGroupingPolicy({"user" + std::to_string(i), "group" + std::to_string(i / 10)});
 
-    params = {"user5001", "data99", "read"};
+    casbin::DataList params = {"user5001", "data99", "read"};
     for (auto _ : state)
         e.Enforce(params);
 }
@@ -97,20 +95,17 @@ static void BenchmarkRBACModelMedium(benchmark::State& state) {
 BENCHMARK(BenchmarkRBACModelMedium);
 
 static void BenchmarkRBACModelLarge(benchmark::State& state) {
-    
     casbin::Enforcer e(rbac_model_path);
-    std::vector<std::string> params(3);
-    std::vector<std::string> params2(2);
 
     // 10000 roles, 1000 resources.
     for(int i = 0; i < 10000; ++i)
-        params = {"group" + std::to_string(i), "data" + std::to_string(i / 10), "read"}, e.AddPolicy(params);
+        e.AddPolicy({"group" + std::to_string(i), "data" + std::to_string(i / 10), "read"});
 
     // 100000 users.
     for(int i = 0; i < 100000; i++)
-        params2 = {"user" + std::to_string(i), "group" + std::to_string(i / 10)}, e.AddGroupingPolicy(params2);
+        e.AddGroupingPolicy({"user" + std::to_string(i), "group" + std::to_string(i / 10)});
 
-    params = {"user50001", "data999", "read"};
+    casbin::DataList params = {"user50001", "data999", "read"};
 
     for(auto _ : state)
         e.Enforce(params);
@@ -120,9 +115,7 @@ static void BenchmarkRBACModelLarge(benchmark::State& state) {
 
 static void BenchmarkRBACModelWithResourceRoles(benchmark::State& state) {
     casbin::Enforcer e(rbac_with_resource_roles_model_path, rbac_with_resource_roles_policy_path);
-    std::vector<std::string> params(3);
-
-    params = {"alice", "data1", "read"};
+    casbin::DataList params = {"alice", "data1", "read"};
     for (auto _ : state)
         e.Enforce(params);
 }
@@ -131,7 +124,7 @@ static void BenchmarkRBACModelWithResourceRoles(benchmark::State& state) {
 
 static void BenchmarkRBACModelWithDomains(benchmark::State& state) {
     casbin::Enforcer e(rbac_with_domains_model_path, rbac_with_domains_policy_path);
-    std::vector<std::string> params = {"alice", "domain1", "data1", "read"};
+    casbin::DataList params = {"alice", "domain1", "data1", "read"};
 
     for(auto _ : state)
         e.Enforce(params);
@@ -152,7 +145,7 @@ BENCHMARK(BenchmarkRBACModelWithDomains);
 
 static void BenchmarkKeyMatchModel(benchmark::State& state) {
     casbin::Enforcer e(keymatch_model_path, keymatch_policy_path);
-    std::vector<std::string> params = {"alice", "/alice_data/resource1", "GET"};
+    casbin::DataList params = {"alice", "/alice_data/resource1", "GET"};
 
     for (auto _ : state)
         e.Enforce(params);
@@ -162,7 +155,7 @@ BENCHMARK(BenchmarkKeyMatchModel);
 
 static void BenchmarkRBACModelWithDeny(benchmark::State& state) {
     casbin::Enforcer e(rbac_with_deny_model_path, rbac_with_deny_policy_path);
-    std::vector<std::string> params = {"alice", "data1", "read"};
+    casbin::DataList params = {"alice", "data1", "read"};
 
     for(auto _ : state)
         e.Enforce(params);
@@ -172,7 +165,7 @@ BENCHMARK(BenchmarkRBACModelWithDeny);
 
 static void BenchmarkPriorityModel(benchmark::State& state) {
     casbin::Enforcer e(priority_model_path, priority_policy_path);
-    std::vector<std::string> params = {"alice", "data1", "read"};
+    casbin::DataList params = {"alice", "data1", "read"};
 
     for(auto _ : state)
         e.Enforce(params);