diff --git a/cpp/unittest/db/db_tests.cpp b/cpp/unittest/db/db_tests.cpp
index 90d35ee8f9..7fd5ed8bc5 100644
--- a/cpp/unittest/db/db_tests.cpp
+++ b/cpp/unittest/db/db_tests.cpp
@@ -10,6 +10,7 @@
 #include "utils.h"
 #include "db/DB.h"
 #include "db/DBImpl.h"
+#include "db/MetaConsts.h"
 
 using namespace zilliz::vecwise;
 
@@ -98,7 +99,7 @@ TEST_F(DBTest2, ARHIVE_DISK_CHECK) {
 
     db_->size(size);
     /* LOG(DEBUG) << "size=" << size; */
-    ASSERT_TRUE(size < 2UL*1024*1024*1024);
+    ASSERT_TRUE(size < 2 * engine::meta::G);
 
     delete [] xb;
 };
@@ -155,7 +156,7 @@ TEST_F(DBTest, DB_TEST) {
 
             START_TIMER;
             stat = db_->search(group_name, k, qb, qxb, results);
-            ss << "Search " << j << " With Size " << (float)(count*group_dim*sizeof(float))/(1024*1024) << " M";
+            ss << "Search " << j << " With Size " << (float)(count*group_dim*sizeof(float))/engine::meta::M << " M";
             STOP_TIMER(ss.str());
 
             ASSERT_STATS(stat);
diff --git a/cpp/unittest/db/meta_tests.cpp b/cpp/unittest/db/meta_tests.cpp
index 1347fcf755..3c8f1802c1 100644
--- a/cpp/unittest/db/meta_tests.cpp
+++ b/cpp/unittest/db/meta_tests.cpp
@@ -13,6 +13,7 @@
 #include "db/DBMetaImpl.h"
 #include "db/Factories.h"
 #include "db/Utils.h"
+#include "db/MetaConsts.h"
 
 using namespace zilliz::vecwise::engine;
 
@@ -116,7 +117,7 @@ TEST_F(MetaTest, ARCHIVE_TEST_DAYS) {
         status = impl.add_group_file(group_file);
         group_file.file_type = meta::GroupFileSchema::NEW;
         int day = rand() % (days_num*2);
-        group_file.created_on = ts - day*24*3600*1000000UL - 10000;
+        group_file.created_on = ts - day*meta::D_SEC*meta::US_PS - 10000;
         status = impl.update_group_file(group_file);
         files.push_back(group_file);
         days.push_back(day);
@@ -160,7 +161,7 @@ TEST_F(MetaTest, ARCHIVE_TEST_DISK) {
     for (auto i=0; i<cnt; ++i) {
         status = impl.add_group_file(group_file);
         group_file.file_type = meta::GroupFileSchema::NEW;
-        group_file.rows = 1024*1024*1024*each_size;
+        group_file.rows = each_size * meta::G;
         status = impl.update_group_file(group_file);
         files.push_back(group_file);
     }