diff --git a/cpp/.gitignore b/cpp/.gitignore
index 03149cde32e944bebf4dfe4026d4870fbbb6a6d9..6c2602d341cba3f789788eb287cf62575928ff5d 100644
--- a/cpp/.gitignore
+++ b/cpp/.gitignore
@@ -7,4 +7,4 @@ lcov_out/
 base.info
 output.info
 output_new.info
-server.info
\ No newline at end of file
+server.info
diff --git a/cpp/CHANGELOG.md b/cpp/CHANGELOG.md
index 03ffe1473195fccc883685f7453148f7b546e11f..966b584694971e8dd3e88ea75e1b232e66c76097 100644
--- a/cpp/CHANGELOG.md
+++ b/cpp/CHANGELOG.md
@@ -11,6 +11,7 @@ Please mark all change in change log and use the ticket from JIRA.
 - MS-149 - Fixed searching only one index file issue in distributed mode
 - MS-153 - fix c_str error when connecting to MySQL
 - MS-157 - fix changelog
+- MS-190 - use env variable to switch mem manager and fix cmake
 
 ## Improvement
 - MS-156 - Add unittest for merge result functions
diff --git a/cpp/cmake/ThirdPartyPackages.cmake b/cpp/cmake/ThirdPartyPackages.cmake
index 2c6c61dbf4dce8ffc19f91421bad7846084526f8..b4b21b8085e4a910e57bfab46d0a4c1be27b3f9a 100644
--- a/cpp/cmake/ThirdPartyPackages.cmake
+++ b/cpp/cmake/ThirdPartyPackages.cmake
@@ -664,7 +664,8 @@ macro(build_knowhere)
             ${EP_COMMON_CMAKE_ARGS}
             "-DCMAKE_INSTALL_PREFIX=${KNOWHERE_PREFIX}"
             -DCMAKE_INSTALL_LIBDIR=lib
-            -DCMAKE_CUDA_COMPILER=/usr/local/cuda/bin/nvcc
+            "-DCMAKE_CUDA_COMPILER=${CMAKE_CUDA_COMPILER}"
+            "-DCUDA_TOOLKIT_ROOT_DIR=${CUDA_TOOLKIT_ROOT_DIR}"
             -DCMAKE_BUILD_TYPE=Release)
 
     externalproject_add(knowhere_ep
diff --git a/cpp/src/CMakeLists.txt b/cpp/src/CMakeLists.txt
index 7a1442cbef71a3499febfb9eaf04faf9f66a57bb..81a085b153b28a6202d74c3ae5b3e60de988a0c4 100644
--- a/cpp/src/CMakeLists.txt
+++ b/cpp/src/CMakeLists.txt
@@ -209,6 +209,7 @@ install(TARGETS milvus_server DESTINATION bin)
 
 install(FILES
         ${CMAKE_BINARY_DIR}/knowhere_ep-prefix/src/knowhere_ep/lib/${CMAKE_SHARED_LIBRARY_PREFIX}tbb${CMAKE_SHARED_LIBRARY_SUFFIX}
+        ${CMAKE_BINARY_DIR}/knowhere_ep-prefix/src/knowhere_ep/lib/${CMAKE_SHARED_LIBRARY_PREFIX}tbb${CMAKE_SHARED_LIBRARY_SUFFIX}.2
         ${CMAKE_BINARY_DIR}/mysqlpp_ep-prefix/src/mysqlpp_ep/lib/${CMAKE_SHARED_LIBRARY_PREFIX}mysqlpp${CMAKE_SHARED_LIBRARY_SUFFIX}
         ${CMAKE_BINARY_DIR}/mysqlpp_ep-prefix/src/mysqlpp_ep/lib/${CMAKE_SHARED_LIBRARY_PREFIX}mysqlpp${CMAKE_SHARED_LIBRARY_SUFFIX}.3
         ${CMAKE_BINARY_DIR}/mysqlpp_ep-prefix/src/mysqlpp_ep/lib/${CMAKE_SHARED_LIBRARY_PREFIX}mysqlpp${CMAKE_SHARED_LIBRARY_SUFFIX}.3.2.4
diff --git a/cpp/src/db/Factories.cpp b/cpp/src/db/Factories.cpp
index 65c7484a502ae5e88ed77f9eba1ccc80890858f4..3cfb9a6eb3c6938c73cfcf232960b194a1096a3a 100644
--- a/cpp/src/db/Factories.cpp
+++ b/cpp/src/db/Factories.cpp
@@ -3,12 +3,14 @@
 // Unauthorized copying of this file, via any medium is strictly prohibited.
 // Proprietary and confidential.
 ////////////////////////////////////////////////////////////////////////////////
-#include <stdlib.h>
+
 #include "Factories.h"
 #include "DBImpl.h"
 #include "MemManager.h"
 #include "NewMemManager.h"
+#include "Exception.h"
 
+#include <stdlib.h>
 #include <time.h>
 #include <sstream>
 #include <iostream>
@@ -16,7 +18,9 @@
 #include <assert.h>
 #include <easylogging++.h>
 #include <regex>
-#include "Exception.h"
+#include <cstdlib>
+#include <string>
+#include <algorithm>
 
 namespace zilliz {
 namespace milvus {
@@ -101,11 +105,17 @@ DB* DBFactory::Build(const Options& options) {
 
 MemManagerAbstractPtr MemManagerFactory::Build(const std::shared_ptr<meta::Meta>& meta,
                                                const Options& options) {
-#ifdef USE_NEW_MEM_MANAGER
+    if (const char* env = getenv("MILVUS_USE_OLD_MEM_MANAGER")) {
+        std::string env_str = env;
+        std::transform(env_str.begin(), env_str.end(), env_str.begin(), ::toupper);
+        if (env_str == "ON") {
+            return std::make_shared<MemManager>(meta, options);
+        }
+        else {
+            return std::make_shared<NewMemManager>(meta, options);
+        }
+    }
     return std::make_shared<NewMemManager>(meta, options);
-#else
-    return std::make_shared<MemManager>(meta, options);
-#endif
 }
 
 } // namespace engine
diff --git a/cpp/thirdparty/knowhere b/cpp/thirdparty/knowhere
index 3a052d063ff9b360529a4a120f9703f00c603437..c3123501d62f69f9eacaa73ee96c0daeb24620a5 160000
--- a/cpp/thirdparty/knowhere
+++ b/cpp/thirdparty/knowhere
@@ -1 +1 @@
-Subproject commit 3a052d063ff9b360529a4a120f9703f00c603437
+Subproject commit c3123501d62f69f9eacaa73ee96c0daeb24620a5
diff --git a/cpp/unittest/db/CMakeLists.txt b/cpp/unittest/db/CMakeLists.txt
index 213eb146ed2873807be41d771b08280d133ebfea..2d360a5d62db13a902fc01e2dfc1f97ad32dac73 100644
--- a/cpp/unittest/db/CMakeLists.txt
+++ b/cpp/unittest/db/CMakeLists.txt
@@ -39,7 +39,7 @@ set(db_test_src
 cuda_add_executable(db_test ${db_test_src})
 
 set(db_libs
-        sqlite3
+        sqlite
         boost_system
         boost_filesystem
         lz4
diff --git a/cpp/unittest/metrics/CMakeLists.txt b/cpp/unittest/metrics/CMakeLists.txt
index d7ae12aff85c969188a053db88a99093c1ad0a0c..e55f99eb3e4abd4b13f5f0faf4757390d86be44e 100644
--- a/cpp/unittest/metrics/CMakeLists.txt
+++ b/cpp/unittest/metrics/CMakeLists.txt
@@ -77,7 +77,7 @@ target_link_libraries(metrics_test
         ${knowhere_libs}
         cudart
         cublas
-        sqlite3
+        sqlite
         boost_system
         boost_filesystem
         lz4