diff --git a/ci/jenkinsfile/milvus_build.groovy b/ci/jenkinsfile/milvus_build.groovy
index db5a0fea7418bf6b5103f36a73cac6f6a4dad2b7..0eb9cd7c999ff272da22e48cb81cb0f0ee6d0d9a 100644
--- a/ci/jenkinsfile/milvus_build.groovy
+++ b/ci/jenkinsfile/milvus_build.groovy
@@ -3,13 +3,16 @@ container('milvus-build-env') {
         gitlabCommitStatus(name: 'Build Engine') {
             dir ("milvus_engine") {
                 try {
-                    def knowhere_build_dir = "${env.WORKSPACE}/milvus_engine/cpp/thirdparty/knowhere/cmake_build"
+                    def knowhere_build_dir = "${env.WORKSPACE}/milvus_engine/cpp/src/core/cmake_build"
 
                     checkout([$class: 'GitSCM', branches: [[name: "${SEMVER}"]], doGenerateSubmoduleConfigurations: false, extensions: [[$class: 'SubmoduleOption',disableSubmodules: false,parentCredentials: true,recursiveSubmodules: true,reference: '',trackingSubmodules: false]], submoduleCfg: [], userRemoteConfigs: [[credentialsId: "${params.GIT_USER}", url: "git@192.168.1.105:megasearch/milvus.git", name: 'origin', refspec: "+refs/heads/${SEMVER}:refs/remotes/origin/${SEMVER}"]]])
+
+                    /*
                     dir ("cpp/thirdparty/knowhere") {
                         checkout([$class: 'GitSCM', branches: [[name: "${SEMVER}"]], doGenerateSubmoduleConfigurations: false, extensions: [[$class: 'SubmoduleOption',disableSubmodules: false,parentCredentials: true,recursiveSubmodules: true,reference: '',trackingSubmodules: false]], submoduleCfg: [], userRemoteConfigs: [[credentialsId: "${params.GIT_USER}", url: "git@192.168.1.105:megasearch/knowhere.git", name: 'origin', refspec: "+refs/heads/${SEMVER}:refs/remotes/origin/${SEMVER}"]]])
                         sh "./build.sh -t ${params.BUILD_TYPE} -p ${knowhere_build_dir} -j"
                     }
+                    */
 
                     dir ("cpp") {
                         sh "git config --global user.email \"test@zilliz.com\""
diff --git a/ci/jenkinsfile/milvus_build_no_ut.groovy b/ci/jenkinsfile/milvus_build_no_ut.groovy
index 750c47e4c33f4eccda9e3b72f83436433dc7f752..8bbb568feeee7f0e68a243f86c1a83db6dd42a24 100644
--- a/ci/jenkinsfile/milvus_build_no_ut.groovy
+++ b/ci/jenkinsfile/milvus_build_no_ut.groovy
@@ -3,14 +3,16 @@ container('milvus-build-env') {
         gitlabCommitStatus(name: 'Build Engine') {
             dir ("milvus_engine") {
                 try {
-                    def knowhere_build_dir = "${env.WORKSPACE}/milvus_engine/cpp/thirdparty/knowhere/cmake_build"
+                    def knowhere_build_dir = "${env.WORKSPACE}/milvus_engine/cpp/src/core/cmake_build"
 
                     checkout([$class: 'GitSCM', branches: [[name: "${SEMVER}"]], doGenerateSubmoduleConfigurations: false, extensions: [[$class: 'SubmoduleOption',disableSubmodules: false,parentCredentials: true,recursiveSubmodules: true,reference: '',trackingSubmodules: false]], submoduleCfg: [], userRemoteConfigs: [[credentialsId: "${params.GIT_USER}", url: "git@192.168.1.105:megasearch/milvus.git", name: 'origin', refspec: "+refs/heads/${SEMVER}:refs/remotes/origin/${SEMVER}"]]])
 
+                    /*
                     dir ("cpp/thirdparty/knowhere") {
                         checkout([$class: 'GitSCM', branches: [[name: "${SEMVER}"]], doGenerateSubmoduleConfigurations: false, extensions: [[$class: 'SubmoduleOption',disableSubmodules: false,parentCredentials: true,recursiveSubmodules: true,reference: '',trackingSubmodules: false]], submoduleCfg: [], userRemoteConfigs: [[credentialsId: "${params.GIT_USER}", url: "git@192.168.1.105:megasearch/knowhere.git", name: 'origin', refspec: "+refs/heads/${SEMVER}:refs/remotes/origin/${SEMVER}"]]])
                         sh "./build.sh -t ${params.BUILD_TYPE} -p ${knowhere_build_dir} -j"
                     }
+                    */
 
                     dir ("cpp") {
                         sh "git config --global user.email \"test@zilliz.com\""
diff --git a/cpp/CHANGELOG.md b/cpp/CHANGELOG.md
index bf3a13da2d1b422c6a287cef4bb78128ebe33837..67a17013f4a97df1a9b46544c66b0ec06adbaa09 100644
--- a/cpp/CHANGELOG.md
+++ b/cpp/CHANGELOG.md
@@ -16,6 +16,9 @@ Please mark all change in change log and use the ticket from JIRA.
 - MS-331 - Crate Table : when table exists, error code is META_FAILED(code=15) rather than ILLEGAL TABLE NAME(code=9))
 - MS-430 - Search no result if index created with FLAT
 - MS-443 - Create index hang again
+- MS-436 - Delete vectors failed if index created with index_type: IVF_FLAT/IVF_SQ8
+- MS-450 - server hang after run stop_server.sh
+- MS-449 - Add vectors twice success, once with ids, the other no ids
 
 ## Improvement
 - MS-327 - Clean code for milvus
@@ -70,6 +73,7 @@ Please mark all change in change log and use the ticket from JIRA.
 - MS-440 - Add DumpTaskTables in sdk
 - MS-442 - Merge Knowhere
 - MS-445 - Rename CopyCompleted to LoadCompleted
+- MS-451 - Update server_config.template file, set GPU compute default
 
 ## New Feature
 - MS-343 - Implement ResourceMgr
diff --git a/cpp/build.sh b/cpp/build.sh
index f61a5ea2e91a0e60ef0a686df3059229eeb48c2a..b2dba3c87086d294d4d24528e1b85cbd51b2db36 100755
--- a/cpp/build.sh
+++ b/cpp/build.sh
@@ -2,7 +2,6 @@
 
 BUILD_TYPE="Debug"
 BUILD_UNITTEST="OFF"
-LICENSE_CHECK="OFF"
 INSTALL_PREFIX=$(pwd)/milvus
 MAKE_CLEAN="OFF"
 BUILD_COVERAGE="OFF"
@@ -11,12 +10,14 @@ PROFILING="OFF"
 BUILD_FAISS_WITH_MKL="OFF"
 USE_JFROG_CACHE="OFF"
 KNOWHERE_BUILD_DIR="`pwd`/src/core/cmake_build"
+KNOWHERE_OPTIONS="-t ${BUILD_TYPE}"
 
-while getopts "p:d:t:k:uhlrcgmj" arg
+while getopts "p:d:t:k:uhrcgmj" arg
 do
         case $arg in
              t)
                 BUILD_TYPE=$OPTARG # BUILD_TYPE
+                KNOWHERE_OPTIONS="-t ${BUILD_TYPE}"
                 ;;
              u)
                 echo "Build and run unittest cases" ;
@@ -28,9 +29,6 @@ do
              d)
                 DB_PATH=$OPTARG
                 ;;
-             l)
-                LICENSE_CHECK="ON"
-                ;;
              r)
                 if [[ -d cmake_build ]]; then
                     rm ./cmake_build -r
@@ -51,6 +49,7 @@ do
                 ;;
              j)
                 USE_JFROG_CACHE="ON"
+                KNOWHERE_OPTIONS="${KNOWHERE_OPTIONS} -j"
                 ;;
              h) # help
                 echo "
@@ -60,7 +59,6 @@ parameter:
 -u: building unit test options(default: OFF)
 -p: install prefix(default: $(pwd)/milvus)
 -d: db path(default: /opt/milvus)
--l: build license version(default: OFF)
 -r: remove previous build directory(default: OFF)
 -c: code coverage(default: OFF)
 -g: profiling(default: OFF)
@@ -85,8 +83,12 @@ if [[ ! -d cmake_build ]]; then
 	MAKE_CLEAN="ON"
 fi
 
+pushd `pwd`/src/core
+./build.sh ${KNOWHERE_OPTIONS}
+popd
+
 cd cmake_build
-git
+
 CUDA_COMPILER=/usr/local/cuda/bin/nvcc
 
 if [[ ${MAKE_CLEAN} == "ON" ]]; then
@@ -94,7 +96,6 @@ if [[ ${MAKE_CLEAN} == "ON" ]]; then
     -DCMAKE_INSTALL_PREFIX=${INSTALL_PREFIX}
     -DCMAKE_BUILD_TYPE=${BUILD_TYPE} \
     -DCMAKE_CUDA_COMPILER=${CUDA_COMPILER} \
-    -DCMAKE_LICENSE_CHECK=${LICENSE_CHECK} \
     -DBUILD_COVERAGE=${BUILD_COVERAGE} \
     -DMILVUS_DB_PATH=${DB_PATH} \
     -DMILVUS_ENABLE_PROFILING=${PROFILING} \
diff --git a/cpp/cmake/ThirdPartyPackages.cmake b/cpp/cmake/ThirdPartyPackages.cmake
index 53d65bd90611c3c60108e61c850799113e692465..f0b353e7b2d7bde7a5c4753e654fa45818285884 100644
--- a/cpp/cmake/ThirdPartyPackages.cmake
+++ b/cpp/cmake/ThirdPartyPackages.cmake
@@ -309,7 +309,8 @@ else()
     # set(FAISS_SOURCE_URL "https://github.com/facebookresearch/faiss/archive/${FAISS_VERSION}.tar.gz")
 endif()
 
-set(FAISS_MD5 "a589663865a8558205533c8ac414278c")
+# set(FAISS_MD5 "a589663865a8558205533c8ac414278c")
+set(FAISS_MD5 "31167ecbd1903fec600dc4ac00b9be9e")
 
 if(DEFINED ENV{MILVUS_KNOWHERE_URL})
     set(KNOWHERE_SOURCE_URL "$ENV{MILVUS_KNOWHERE_URL}")
diff --git a/cpp/conf/server_config.template b/cpp/conf/server_config.template
index 386b61d1f102f086bd38643da0ea1c876cf69284..daf75459da9d3b85b3f0d3df1c82267eeefe73b4 100644
--- a/cpp/conf/server_config.template
+++ b/cpp/conf/server_config.template
@@ -64,9 +64,9 @@ resource_config:
       memory: 64
       device_id: 0
       enable_loader: true
-      enable_executor: true
+      enable_executor: false
 
-    gtx1060:
+    gpu0:
       type: GPU
       memory: 6
       device_id: 0
@@ -80,10 +80,17 @@ resource_config:
       enable_loader: false
       enable_executor: false
 
+#    gtx1660:
+#      type: GPU
+#      memory: 6
+#      device_id: 1
+#      enable_loader: true
+#      enable_executor: true
+
   # connection list, length: 0~N
   # format: -${resource_name}===${resource_name}
   connections:
     - ssda===cpu
-    - cpu===gtx1060
-    - cpu===gtx1660
+    - cpu===gpu0
+#    - cpu===gtx1660
 
diff --git a/cpp/src/core/cmake/ThirdPartyPackages.cmake b/cpp/src/core/cmake/ThirdPartyPackages.cmake
index 981e1bd558a29e1c01d2b9619b30767ec2a7d1ee..945f50fb73d080e836b35f13584fc1726dc5b7ed 100644
--- a/cpp/src/core/cmake/ThirdPartyPackages.cmake
+++ b/cpp/src/core/cmake/ThirdPartyPackages.cmake
@@ -260,7 +260,8 @@ else()
 #    set(FAISS_SOURCE_URL "${CMAKE_SOURCE_DIR}/thirdparty/faiss-1.5.3")
     message(STATUS ${FAISS_SOURCE_URL})
 endif()
-set(FAISS_MD5 "a589663865a8558205533c8ac414278c")
+# set(FAISS_MD5 "a589663865a8558205533c8ac414278c")
+set(FAISS_MD5 "31167ecbd1903fec600dc4ac00b9be9e")
 
 if(DEFINED ENV{KNOWHERE_ARROW_URL})
     set(ARROW_SOURCE_URL "$ENV{KNOWHERE_ARROW_URL}")
@@ -924,7 +925,7 @@ macro(build_faiss)
     if(USE_JFROG_CACHE STREQUAL "ON")
 #        Check_Last_Modify("${CMAKE_SOURCE_DIR}/thirdparty/faiss_cache_check_lists.txt" "${CMAKE_SOURCE_DIR}" FAISS_LAST_MODIFIED_COMMIT_ID)
         string(MD5 FAISS_COMBINE_MD5 "${FAISS_MD5}${LAPACK_MD5}${OPENBLAS_MD5}")
-        string(MD5 FAISS_COMBINE_MD5 "${FAISS_LAST_MODIFIED_COMMIT_ID}${LAPACK_MD5}${OPENBLAS_MD5}")
+        # string(MD5 FAISS_COMBINE_MD5 "${FAISS_LAST_MODIFIED_COMMIT_ID}${LAPACK_MD5}${OPENBLAS_MD5}")
         set(FAISS_CACHE_PACKAGE_NAME "faiss_${FAISS_COMBINE_MD5}.tar.gz")
         set(FAISS_CACHE_URL "${JFROG_ARTFACTORY_CACHE_URL}/${FAISS_CACHE_PACKAGE_NAME}")
         set(FAISS_CACHE_PACKAGE_PATH "${THIRDPARTY_PACKAGE_CACHE}/${FAISS_CACHE_PACKAGE_NAME}")
diff --git a/cpp/src/core/thirdparty/faiss_cache_check_lists.txt b/cpp/src/core/thirdparty/faiss_cache_check_lists.txt
new file mode 100644
index 0000000000000000000000000000000000000000..ce75614ca5b2275a61a62e7fd5125493b43baabc
--- /dev/null
+++ b/cpp/src/core/thirdparty/faiss_cache_check_lists.txt
@@ -0,0 +1,13 @@
+# source
+src/
+include/
+
+# third party
+thirdparty/
+
+# cmake
+cmake/
+CMakeLists.txt
+
+# script
+build.sh
\ No newline at end of file
diff --git a/cpp/src/db/DB.h b/cpp/src/db/DB.h
index 908714a08a61a8a7e50a379b49bbf8f413f09b12..d493c0f78cad2cacc77ac5edd7085dbe78a122b6 100644
--- a/cpp/src/db/DB.h
+++ b/cpp/src/db/DB.h
@@ -22,6 +22,9 @@ class DB {
 public:
     static void Open(const Options& options, DB** dbptr);
 
+    virtual Status Start() = 0;
+    virtual Status Stop() = 0;
+
     virtual Status CreateTable(meta::TableSchema& table_schema_) = 0;
     virtual Status DeleteTable(const std::string& table_id, const meta::DatesT& dates) = 0;
     virtual Status DescribeTable(meta::TableSchema& table_schema_) = 0;
diff --git a/cpp/src/db/DBImpl.cpp b/cpp/src/db/DBImpl.cpp
index 4f9cd1e792b6bd6d380d6b9e7b2fc88eb66f7a02..b744899d561b98e5a0bd66b62847412158b37e60 100644
--- a/cpp/src/db/DBImpl.cpp
+++ b/cpp/src/db/DBImpl.cpp
@@ -41,17 +41,55 @@ constexpr uint64_t INDEX_ACTION_INTERVAL = 1;
 
 DBImpl::DBImpl(const Options& options)
     : options_(options),
-      shutting_down_(false),
+      shutting_down_(true),
       compact_thread_pool_(1, 1),
       index_thread_pool_(1, 1) {
     meta_ptr_ = DBMetaImplFactory::Build(options.meta, options.mode);
     mem_mgr_ = MemManagerFactory::Build(meta_ptr_, options_);
-    if (options.mode != Options::MODE::READ_ONLY) {
+    Start();
+}
+
+DBImpl::~DBImpl() {
+    Stop();
+}
+
+Status DBImpl::Start() {
+    if (!shutting_down_.load(std::memory_order_acquire)){
+        return Status::OK();
+    }
+
+    //for distribute version, some nodes are read only
+    if (options_.mode != Options::MODE::READ_ONLY) {
         ENGINE_LOG_TRACE << "StartTimerTasks";
-        StartTimerTasks();
+        bg_timer_thread_ = std::thread(&DBImpl::BackgroundTimerTask, this);
     }
 
+    shutting_down_.store(false, std::memory_order_release);
 
+    return Status::OK();
+}
+
+Status DBImpl::Stop() {
+    if (shutting_down_.load(std::memory_order_acquire)){
+        return Status::OK();
+    }
+
+    shutting_down_.store(true, std::memory_order_release);
+    bg_timer_thread_.join();
+
+    //wait compaction/buildindex finish
+    for(auto& result : compact_thread_results_) {
+        result.wait();
+    }
+
+    for(auto& result : index_thread_results_) {
+        result.wait();
+    }
+
+    //makesure all memory data serialized
+    MemSerialize();
+
+    return Status::OK();
 }
 
 Status DBImpl::CreateTable(meta::TableSchema& table_schema) {
@@ -162,7 +200,7 @@ Status DBImpl::Query(const std::string &table_id, uint64_t k, uint64_t nq, uint6
                       const float *vectors, QueryResults &results) {
     server::CollectQueryMetrics metrics(nq);
 
-    meta::DatesT dates = {meta::Meta::GetDate()};
+    meta::DatesT dates = {utils::GetDate()};
     Status result = Query(table_id, k, nq, nprobe, vectors, dates, results);
 
     return result;
@@ -278,10 +316,6 @@ Status DBImpl::QueryAsync(const std::string& table_id, const meta::TableFilesSch
     return Status::OK();
 }
 
-void DBImpl::StartTimerTasks() {
-    bg_timer_thread_ = std::thread(&DBImpl::BackgroundTimerTask, this);
-}
-
 void DBImpl::BackgroundTimerTask() {
     Status status;
     server::SystemInfo::GetInstance().Init();
@@ -741,13 +775,6 @@ Status DBImpl::Size(uint64_t& result) {
     return  meta_ptr_->Size(result);
 }
 
-DBImpl::~DBImpl() {
-    shutting_down_.store(true, std::memory_order_release);
-    bg_timer_thread_.join();
-    std::set<std::string> ids;
-    mem_mgr_->Serialize(ids);
-}
-
 } // namespace engine
 } // namespace milvus
 } // namespace zilliz
diff --git a/cpp/src/db/DBImpl.h b/cpp/src/db/DBImpl.h
index b8f43daf83724e5df0a224c6687cd14dcd42fcf0..7fb8295b2f37e72054e1acaaa9621f4d94fe3840 100644
--- a/cpp/src/db/DBImpl.h
+++ b/cpp/src/db/DBImpl.h
@@ -36,6 +36,9 @@ class DBImpl : public DB {
 
     explicit DBImpl(const Options &options);
 
+    Status Start() override;
+    Status Stop() override;
+
     Status CreateTable(meta::TableSchema &table_schema) override;
 
     Status DeleteTable(const std::string &table_id, const meta::DatesT &dates) override;
@@ -91,18 +94,15 @@ class DBImpl : public DB {
     ~DBImpl() override;
 
  private:
-    Status
-    QueryAsync(const std::string &table_id,
-               const meta::TableFilesSchema &files,
-               uint64_t k,
-               uint64_t nq,
-               uint64_t nprobe,
-               const float *vectors,
-               const meta::DatesT &dates,
-               QueryResults &results);
-
-
-    void StartTimerTasks();
+    Status QueryAsync(const std::string &table_id,
+                      const meta::TableFilesSchema &files,
+                      uint64_t k,
+                      uint64_t nq,
+                      uint64_t nprobe,
+                      const float *vectors,
+                      const meta::DatesT &dates,
+                      QueryResults &results);
+
     void BackgroundTimerTask();
 
     void StartMetricTask();
diff --git a/cpp/src/db/Utils.cpp b/cpp/src/db/Utils.cpp
index 4eec3346b0260b627796f9a191d6479d2d0f5455..efe238d86f4120e343b64725d383bfc199087749 100644
--- a/cpp/src/db/Utils.cpp
+++ b/cpp/src/db/Utils.cpp
@@ -152,8 +152,33 @@ bool IsSameIndex(const TableIndex& index1, const TableIndex& index2) {
         && index1.metric_type_ == index2.metric_type_;
 }
 
-bool UserDefinedId(int64_t flag) {
-    return flag & meta::FLAG_MASK_USERID;
+meta::DateT GetDate(const std::time_t& t, int day_delta) {
+    struct tm ltm;
+    localtime_r(&t, &ltm);
+    if (day_delta > 0) {
+        do {
+            ++ltm.tm_mday;
+            --day_delta;
+        } while(day_delta > 0);
+        mktime(&ltm);
+    } else if (day_delta < 0) {
+        do {
+            --ltm.tm_mday;
+            ++day_delta;
+        } while(day_delta < 0);
+        mktime(&ltm);
+    } else {
+        ltm.tm_mday;
+    }
+    return ltm.tm_year*10000 + ltm.tm_mon*100 + ltm.tm_mday;
+}
+
+meta::DateT GetDateWithDelta(int day_delta) {
+    return GetDate(std::time(nullptr), day_delta);
+}
+
+meta::DateT GetDate() {
+    return GetDate(std::time(nullptr), 0);
 }
 
 } // namespace utils
diff --git a/cpp/src/db/Utils.h b/cpp/src/db/Utils.h
index d6244ebc916b3859aed9c8a18d5c745bed652eaf..2094250a1f3c5fd71b81d742004033b5edaca1cb 100644
--- a/cpp/src/db/Utils.h
+++ b/cpp/src/db/Utils.h
@@ -10,6 +10,7 @@
 #include "db/Types.h"
 
 #include <string>
+#include <ctime>
 
 namespace zilliz {
 namespace milvus {
@@ -27,7 +28,9 @@ Status DeleteTableFilePath(const DBMetaOptions& options, meta::TableFileSchema&
 
 bool IsSameIndex(const TableIndex& index1, const TableIndex& index2);
 
-bool UserDefinedId(int64_t flag);
+meta::DateT GetDate(const std::time_t &t, int day_delta = 0);
+meta::DateT GetDate();
+meta::DateT GetDateWithDelta(int day_delta);
 
 } // namespace utils
 } // namespace engine
diff --git a/cpp/src/db/meta/Meta.cpp b/cpp/src/db/meta/Meta.cpp
deleted file mode 100644
index a86051a1c483c4edcaee42e20d4ad840e3de6a2a..0000000000000000000000000000000000000000
--- a/cpp/src/db/meta/Meta.cpp
+++ /dev/null
@@ -1,50 +0,0 @@
-/*******************************************************************************
- * Copyright 上海赜睿信息科技有限公司(Zilliz) - All Rights Reserved
- * Unauthorized copying of this file, via any medium is strictly prohibited.
- * Proprietary and confidential.
- ******************************************************************************/
-#include "Meta.h"
-
-#include <ctime>
-#include <stdio.h>
-
-namespace zilliz {
-namespace milvus {
-namespace engine {
-namespace meta {
-
-Meta::~Meta() = default;
-
-DateT Meta::GetDate(const std::time_t& t, int day_delta) {
-    struct tm ltm;
-    localtime_r(&t, &ltm);
-    if (day_delta > 0) {
-        do {
-            ++ltm.tm_mday;
-            --day_delta;
-        } while(day_delta > 0);
-        mktime(&ltm);
-    } else if (day_delta < 0) {
-        do {
-            --ltm.tm_mday;
-            ++day_delta;
-        } while(day_delta < 0);
-        mktime(&ltm);
-    } else {
-        ltm.tm_mday;
-    }
-    return ltm.tm_year*10000 + ltm.tm_mon*100 + ltm.tm_mday;
-}
-
-DateT Meta::GetDateWithDelta(int day_delta) {
-    return GetDate(std::time(nullptr), day_delta);
-}
-
-DateT Meta::GetDate() {
-    return GetDate(std::time(nullptr), 0);
-}
-
-} // namespace meta
-} // namespace engine
-} // namespace milvus
-} // namespace zilliz
diff --git a/cpp/src/db/meta/Meta.h b/cpp/src/db/meta/Meta.h
index b7210815ddf19ebb6a18c92c13e2ccc5dbec4192..8d5dd63a0ac9f94fba3fec91c56d5b729c04aa66 100644
--- a/cpp/src/db/meta/Meta.h
+++ b/cpp/src/db/meta/Meta.h
@@ -11,7 +11,6 @@
 #include "db/Types.h"
 
 #include <cstddef>
-#include <ctime>
 #include <memory>
 
 namespace zilliz {
@@ -19,105 +18,70 @@ namespace milvus {
 namespace engine {
 namespace meta {
 
-
 class Meta {
  public:
     using Ptr = std::shared_ptr<Meta>;
 
-    virtual
-    ~Meta() = 0;
-
-    virtual Status
-    CreateTable(TableSchema &table_schema) = 0;
-
-    virtual Status
-    DescribeTable(TableSchema &table_schema) = 0;
-
-    virtual Status
-    HasTable(const std::string &table_id, bool &has_or_not) = 0;
+    virtual ~Meta() = default;
 
-    virtual Status
-    AllTables(std::vector<TableSchema> &table_schema_array) = 0;
+    virtual Status CreateTable(TableSchema &table_schema) = 0;
 
-    virtual Status
-    UpdateTableIndexParam(const std::string &table_id, const TableIndex& index) = 0;
+    virtual Status DescribeTable(TableSchema &table_schema) = 0;
 
-    virtual Status
-    UpdateTableFlag(const std::string &table_id, int64_t flag) = 0;
+    virtual Status HasTable(const std::string &table_id, bool &has_or_not) = 0;
 
-    virtual Status
-    DeleteTable(const std::string &table_id) = 0;
+    virtual Status AllTables(std::vector<TableSchema> &table_schema_array) = 0;
 
-    virtual Status
-    DeleteTableFiles(const std::string &table_id) = 0;
+    virtual Status UpdateTableIndexParam(const std::string &table_id, const TableIndex& index) = 0;
 
-    virtual Status
-    CreateTableFile(TableFileSchema &file_schema) = 0;
+    virtual Status UpdateTableFlag(const std::string &table_id, int64_t flag) = 0;
 
-    virtual Status
-    DropPartitionsByDates(const std::string &table_id, const DatesT &dates) = 0;
+    virtual Status DeleteTable(const std::string &table_id) = 0;
 
-    virtual Status
-    GetTableFiles(const std::string &table_id, const std::vector<size_t> &ids, TableFilesSchema &table_files) = 0;
+    virtual Status DeleteTableFiles(const std::string &table_id) = 0;
 
-    virtual Status
-    UpdateTableFilesToIndex(const std::string &table_id) = 0;
+    virtual Status CreateTableFile(TableFileSchema &file_schema) = 0;
 
-    virtual Status
-    UpdateTableFile(TableFileSchema &file_schema) = 0;
+    virtual Status DropPartitionsByDates(const std::string &table_id, const DatesT &dates) = 0;
 
-    virtual Status
-    UpdateTableFiles(TableFilesSchema &files) = 0;
+    virtual Status GetTableFiles(const std::string &table_id,
+                                 const std::vector<size_t> &ids,
+                                 TableFilesSchema &table_files) = 0;
 
-    virtual Status
-    FilesToSearch(const std::string &table_id,
-                  const std::vector<size_t> &ids,
-                  const DatesT &partition,
-                  DatePartionedTableFilesSchema &files) = 0;
+    virtual Status UpdateTableFilesToIndex(const std::string &table_id) = 0;
 
-    virtual Status
-    FilesToMerge(const std::string &table_id, DatePartionedTableFilesSchema &files) = 0;
+    virtual Status UpdateTableFile(TableFileSchema &file_schema) = 0;
 
-    virtual Status
-    Size(uint64_t &result) = 0;
+    virtual Status UpdateTableFiles(TableFilesSchema &files) = 0;
 
-    virtual Status
-    Archive() = 0;
+    virtual Status FilesToSearch(const std::string &table_id,
+                                 const std::vector<size_t> &ids,
+                                 const DatesT &partition,
+                                 DatePartionedTableFilesSchema &files) = 0;
 
-    virtual Status
-    FilesToIndex(TableFilesSchema &) = 0;
+    virtual Status FilesToMerge(const std::string &table_id, DatePartionedTableFilesSchema &files) = 0;
 
-    virtual Status
-    FilesByType(const std::string &table_id,
-                const std::vector<int> &file_types,
-                std::vector<std::string>& file_ids) = 0;
+    virtual Status Size(uint64_t &result) = 0;
 
-    virtual Status
-    DescribeTableIndex(const std::string &table_id, TableIndex& index) = 0;
+    virtual Status Archive() = 0;
 
-    virtual Status
-    DropTableIndex(const std::string &table_id) = 0;
+    virtual Status FilesToIndex(TableFilesSchema &) = 0;
 
-    virtual Status
-    CleanUp() = 0;
+    virtual Status FilesByType(const std::string &table_id,
+                               const std::vector<int> &file_types,
+                               std::vector<std::string>& file_ids) = 0;
 
-    virtual Status
-    CleanUpFilesWithTTL(uint16_t) = 0;
+    virtual Status DescribeTableIndex(const std::string &table_id, TableIndex& index) = 0;
 
-    virtual Status
-    DropAll() = 0;
+    virtual Status DropTableIndex(const std::string &table_id) = 0;
 
-    virtual Status
-    Count(const std::string &table_id, uint64_t &result) = 0;
+    virtual Status CleanUp() = 0;
 
-    static DateT
-    GetDate(const std::time_t &t, int day_delta = 0);
+    virtual Status CleanUpFilesWithTTL(uint16_t) = 0;
 
-    static DateT
-    GetDate();
+    virtual Status DropAll() = 0;
 
-    static DateT
-    GetDateWithDelta(int day_delta);
+    virtual Status Count(const std::string &table_id, uint64_t &result) = 0;
 
 }; // MetaData
 
diff --git a/cpp/src/db/meta/MetaTypes.h b/cpp/src/db/meta/MetaTypes.h
index e4c68decbc03acf4663904c661725ce3a2774205..e31be40ddc25c72476007cb66483b59f7d978bdd 100644
--- a/cpp/src/db/meta/MetaTypes.h
+++ b/cpp/src/db/meta/MetaTypes.h
@@ -22,7 +22,8 @@ constexpr int32_t DEFAULT_NLIST = 16384;
 constexpr int32_t DEFAULT_METRIC_TYPE = (int)MetricType::L2;
 constexpr int32_t DEFAULT_INDEX_FILE_SIZE = ONE_GB;
 
-constexpr int64_t FLAG_MASK_USERID = 1;
+constexpr int64_t FLAG_MASK_NO_USERID = 0x1;
+constexpr int64_t FLAG_MASK_HAS_USERID = 0x1<<1;
 
 typedef int DateT;
 const DateT EmptyDate = -1;
diff --git a/cpp/src/db/meta/MySQLMetaImpl.cpp b/cpp/src/db/meta/MySQLMetaImpl.cpp
index b14ac11569470a00d97f2266e9e9100a7b9cce95..beae3fa1e98a02305b812a63e99c2f4072305d72 100644
--- a/cpp/src/db/meta/MySQLMetaImpl.cpp
+++ b/cpp/src/db/meta/MySQLMetaImpl.cpp
@@ -41,6 +41,18 @@ Status HandleException(const std::string &desc, std::exception &e) {
 
 }
 
+MySQLMetaImpl::MySQLMetaImpl(const DBMetaOptions &options_, const int &mode)
+    : options_(options_),
+      mode_(mode) {
+    Initialize();
+}
+
+MySQLMetaImpl::~MySQLMetaImpl() {
+    if (mode_ != Options::MODE::READ_ONLY) {
+        CleanUp();
+    }
+}
+
 Status MySQLMetaImpl::NextTableId(std::string &table_id) {
     std::stringstream ss;
     SimpleIDGenerator g;
@@ -57,12 +69,6 @@ Status MySQLMetaImpl::NextFileId(std::string &file_id) {
     return Status::OK();
 }
 
-MySQLMetaImpl::MySQLMetaImpl(const DBMetaOptions &options_, const int &mode)
-    : options_(options_),
-      mode_(mode) {
-    Initialize();
-}
-
 Status MySQLMetaImpl::Initialize() {
     if (!boost::filesystem::is_directory(options_.path)) {
         auto ret = boost::filesystem::create_directory(options_.path);
@@ -202,15 +208,6 @@ Status MySQLMetaImpl::DropPartitionsByDates(const std::string &table_id,
     }
 
     try {
-
-        auto yesterday = GetDateWithDelta(-1);
-
-        for (auto &date : dates) {
-            if (date >= yesterday) {
-                return Status::Error("Could not delete partitions within 2 days");
-            }
-        }
-
         std::stringstream dateListSS;
         for (auto &date : dates) {
             dateListSS << std::to_string(date) << ", ";
@@ -229,7 +226,8 @@ Status MySQLMetaImpl::DropPartitionsByDates(const std::string &table_id,
             Query dropPartitionsByDatesQuery = connectionPtr->query();
 
             dropPartitionsByDatesQuery << "UPDATE TableFiles " <<
-                                       "SET file_type = " << std::to_string(TableFileSchema::TO_DELETE) << " " <<
+                                       "SET file_type = " << std::to_string(TableFileSchema::TO_DELETE) << "," <<
+                                       "updated_time = " << utils::GetMicroSecTimeStamp() << " " <<
                                        "WHERE table_id = " << quote << table_id << " AND " <<
                                        "date in (" << dateListStr << ");";
 
@@ -877,7 +875,7 @@ Status MySQLMetaImpl::AllTables(std::vector<TableSchema> &table_schema_array) {
 
 Status MySQLMetaImpl::CreateTableFile(TableFileSchema &file_schema) {
     if (file_schema.date_ == EmptyDate) {
-        file_schema.date_ = Meta::GetDate();
+        file_schema.date_ = utils::GetDate();
     }
     TableSchema table_schema;
     table_schema.table_id_ = file_schema.table_id_;
@@ -2031,12 +2029,6 @@ Status MySQLMetaImpl::DropAll() {
     return Status::OK();
 }
 
-MySQLMetaImpl::~MySQLMetaImpl() {
-    if (mode_ != Options::MODE::READ_ONLY) {
-        CleanUp();
-    }
-}
-
 } // namespace meta
 } // namespace engine
 } // namespace milvus
diff --git a/cpp/src/db/meta/MySQLMetaImpl.h b/cpp/src/db/meta/MySQLMetaImpl.h
index f5454d2f5f5f9c2bc5e3dfff36ee6b3a61511602..08897cbe30bf37260dd793b0ae0f54d755787862 100644
--- a/cpp/src/db/meta/MySQLMetaImpl.h
+++ b/cpp/src/db/meta/MySQLMetaImpl.h
@@ -24,6 +24,7 @@ using namespace mysqlpp;
 class MySQLMetaImpl : public Meta {
  public:
     MySQLMetaImpl(const DBMetaOptions &options_, const int &mode);
+    ~MySQLMetaImpl();
 
     Status CreateTable(TableSchema &table_schema) override;
 
@@ -86,8 +87,6 @@ class MySQLMetaImpl : public Meta {
 
     Status Count(const std::string &table_id, uint64_t &result) override;
 
-    virtual ~MySQLMetaImpl();
-
  private:
     Status NextFileId(std::string &file_id);
     Status NextTableId(std::string &table_id);
diff --git a/cpp/src/db/meta/SqliteMetaImpl.cpp b/cpp/src/db/meta/SqliteMetaImpl.cpp
index 0b111b255a39f920b6a6defc43cc61a2f09dd5e9..73b4501aecbe07957d588eccdcf2095f2f3d1530 100644
--- a/cpp/src/db/meta/SqliteMetaImpl.cpp
+++ b/cpp/src/db/meta/SqliteMetaImpl.cpp
@@ -68,6 +68,15 @@ using ConnectorT = decltype(StoragePrototype(""));
 static std::unique_ptr<ConnectorT> ConnectorPtr;
 using ConditionT = decltype(c(&TableFileSchema::id_) == 1UL);
 
+SqliteMetaImpl::SqliteMetaImpl(const DBMetaOptions &options_)
+    : options_(options_) {
+    Initialize();
+}
+
+SqliteMetaImpl::~SqliteMetaImpl() {
+    CleanUp();
+}
+
 Status SqliteMetaImpl::NextTableId(std::string &table_id) {
     std::stringstream ss;
     SimpleIDGenerator g;
@@ -84,11 +93,6 @@ Status SqliteMetaImpl::NextFileId(std::string &file_id) {
     return Status::OK();
 }
 
-SqliteMetaImpl::SqliteMetaImpl(const DBMetaOptions &options_)
-    : options_(options_) {
-    Initialize();
-}
-
 Status SqliteMetaImpl::Initialize() {
     if (!boost::filesystem::is_directory(options_.path)) {
         auto ret = boost::filesystem::create_directory(options_.path);
@@ -111,7 +115,7 @@ Status SqliteMetaImpl::Initialize() {
 
 // PXU TODO: Temp solution. Will fix later
 Status SqliteMetaImpl::DropPartitionsByDates(const std::string &table_id,
-                                         const DatesT &dates) {
+                                             const DatesT &dates) {
     if (dates.size() == 0) {
         return Status::OK();
     }
@@ -124,20 +128,13 @@ Status SqliteMetaImpl::DropPartitionsByDates(const std::string &table_id,
     }
 
     try {
-        auto yesterday = GetDateWithDelta(-1);
-
-        for (auto &date : dates) {
-            if (date >= yesterday) {
-                return Status::Error("Could not delete partitions with 2 days");
-            }
-        }
-
         //multi-threads call sqlite update may get exception('bad logic', etc), so we add a lock here
         std::lock_guard<std::mutex> meta_lock(meta_mutex_);
 
         ConnectorPtr->update_all(
             set(
-                c(&TableFileSchema::file_type_) = (int) TableFileSchema::TO_DELETE
+                c(&TableFileSchema::file_type_) = (int) TableFileSchema::TO_DELETE,
+                c(&TableFileSchema::updated_time_) = utils::GetMicroSecTimeStamp()
             ),
             where(
                 c(&TableFileSchema::table_id_) == table_id and
@@ -543,7 +540,7 @@ Status SqliteMetaImpl::AllTables(std::vector<TableSchema>& table_schema_array) {
 
 Status SqliteMetaImpl::CreateTableFile(TableFileSchema &file_schema) {
     if (file_schema.date_ == EmptyDate) {
-        file_schema.date_ = Meta::GetDate();
+        file_schema.date_ = utils::GetDate();
     }
     TableSchema table_schema;
     table_schema.table_id_ = file_schema.table_id_;
@@ -1214,10 +1211,6 @@ Status SqliteMetaImpl::DropAll() {
     return Status::OK();
 }
 
-SqliteMetaImpl::~SqliteMetaImpl() {
-    CleanUp();
-}
-
 } // namespace meta
 } // namespace engine
 } // namespace milvus
diff --git a/cpp/src/db/meta/SqliteMetaImpl.h b/cpp/src/db/meta/SqliteMetaImpl.h
index 4a780d9084197f06c2a96ca0823566a34d5e5641..ad0d21f5e958636cef7a16b93a701125c05f146a 100644
--- a/cpp/src/db/meta/SqliteMetaImpl.h
+++ b/cpp/src/db/meta/SqliteMetaImpl.h
@@ -20,6 +20,7 @@ auto StoragePrototype(const std::string &path);
 class SqliteMetaImpl : public Meta {
  public:
     explicit SqliteMetaImpl(const DBMetaOptions &options_);
+    ~SqliteMetaImpl();
 
     Status CreateTable(TableSchema &table_schema) override;
 
@@ -80,8 +81,6 @@ class SqliteMetaImpl : public Meta {
 
     Status Count(const std::string &table_id, uint64_t &result) override;
 
-    ~SqliteMetaImpl() override;
-
  private:
     Status NextFileId(std::string &file_id);
     Status NextTableId(std::string &table_id);
diff --git a/cpp/src/metrics/Metrics.h b/cpp/src/metrics/Metrics.h
index 48f9f2b1118409a1e403a0618bf74ba8013095df..eb6e500f26a3439c14a188a33cd5e7da81acfec3 100644
--- a/cpp/src/metrics/Metrics.h
+++ b/cpp/src/metrics/Metrics.h
@@ -37,21 +37,22 @@ public:
     }
 
     ~CollectInsertMetrics() {
-        auto end_time = METRICS_NOW_TIME;
-        auto total_time = METRICS_MICROSECONDS(start_time_, end_time);
-        double avg_time = total_time / n_;
-        for (int i = 0; i < n_; ++i) {
-            Metrics::GetInstance().AddVectorsDurationHistogramOberve(avg_time);
-        }
+        if(n_ > 0) {
+            auto end_time = METRICS_NOW_TIME;
+            auto total_time = METRICS_MICROSECONDS(start_time_, end_time);
+            double avg_time = total_time / n_;
+            for (int i = 0; i < n_; ++i) {
+                Metrics::GetInstance().AddVectorsDurationHistogramOberve(avg_time);
+            }
 
-        //    server::Metrics::GetInstance().add_vector_duration_seconds_quantiles().Observe((average_time));
-        if (status_.ok()) {
-            server::Metrics::GetInstance().AddVectorsSuccessTotalIncrement(n_);
-            server::Metrics::GetInstance().AddVectorsSuccessGaugeSet(n_);
-        }
-        else {
-            server::Metrics::GetInstance().AddVectorsFailTotalIncrement(n_);
-            server::Metrics::GetInstance().AddVectorsFailGaugeSet(n_);
+            //    server::Metrics::GetInstance().add_vector_duration_seconds_quantiles().Observe((average_time));
+            if (status_.ok()) {
+                server::Metrics::GetInstance().AddVectorsSuccessTotalIncrement(n_);
+                server::Metrics::GetInstance().AddVectorsSuccessGaugeSet(n_);
+            } else {
+                server::Metrics::GetInstance().AddVectorsFailTotalIncrement(n_);
+                server::Metrics::GetInstance().AddVectorsFailGaugeSet(n_);
+            }
         }
     }
 
@@ -69,14 +70,16 @@ public:
     }
 
     ~CollectQueryMetrics() {
-        auto end_time = METRICS_NOW_TIME;
-        auto total_time = METRICS_MICROSECONDS(start_time_, end_time);
-        for (int i = 0; i < nq_; ++i) {
-            server::Metrics::GetInstance().QueryResponseSummaryObserve(total_time);
+        if(nq_ > 0) {
+            auto end_time = METRICS_NOW_TIME;
+            auto total_time = METRICS_MICROSECONDS(start_time_, end_time);
+            for (int i = 0; i < nq_; ++i) {
+                server::Metrics::GetInstance().QueryResponseSummaryObserve(total_time);
+            }
+            auto average_time = total_time / nq_;
+            server::Metrics::GetInstance().QueryVectorResponseSummaryObserve(average_time, nq_);
+            server::Metrics::GetInstance().QueryVectorResponsePerSecondGaugeSet(double(nq_) / total_time);
         }
-        auto average_time = total_time / nq_;
-        server::Metrics::GetInstance().QueryVectorResponseSummaryObserve(average_time, nq_);
-        server::Metrics::GetInstance().QueryVectorResponsePerSecondGaugeSet(double (nq_) / total_time);
     }
 
 private:
diff --git a/cpp/src/scheduler/SchedInst.cpp b/cpp/src/scheduler/SchedInst.cpp
index 972c2e260658f2ba56a6e868ec19777b7f92ff39..3ee8cbfdb6e4197669a5758f742a5fc6996fc532 100644
--- a/cpp/src/scheduler/SchedInst.cpp
+++ b/cpp/src/scheduler/SchedInst.cpp
@@ -7,6 +7,7 @@
 #include "SchedInst.h"
 #include "server/ServerConfig.h"
 #include "ResourceFactory.h"
+#include "knowhere/index/vector_index/gpu_ivf.h"
 
 namespace zilliz {
 namespace milvus {
@@ -19,7 +20,7 @@ SchedulerPtr SchedInst::instance = nullptr;
 std::mutex SchedInst::mutex_;
 
 void
-SchedServInit() {
+StartSchedulerService() {
     server::ConfigNode &config = server::ServerConfig::GetInstance().GetConfig(server::CONFIG_RESOURCE);
     auto resources = config.GetChild(server::CONFIG_RESOURCES).GetChildren();
     for (auto &resource : resources) {
@@ -36,8 +37,12 @@ SchedServInit() {
                                                                device_id,
                                                                enable_loader,
                                                                enable_executor));
+
+        knowhere::FaissGpuResourceMgr::GetInstance().InitDevice(device_id);
     }
 
+    knowhere::FaissGpuResourceMgr::GetInstance().InitResource();
+
     auto default_connection = Connection("default_connection", 500.0);
     auto connections = config.GetSequence(server::CONFIG_RESOURCE_CONNECTIONS);
     for (auto &conn : connections) {
@@ -52,6 +57,11 @@ SchedServInit() {
     SchedInst::GetInstance()->Start();
 }
 
+void
+StopSchedulerService() {
+    ResMgrInst::GetInstance()->Stop();
+    SchedInst::GetInstance()->Stop();
+}
 }
 }
 }
diff --git a/cpp/src/scheduler/SchedInst.h b/cpp/src/scheduler/SchedInst.h
index 3ae36827a8211596aa28cfe02bfb329579478fa1..92f3575ebc20c846670ef0314a344a3511a86ff3 100644
--- a/cpp/src/scheduler/SchedInst.h
+++ b/cpp/src/scheduler/SchedInst.h
@@ -53,7 +53,10 @@ private:
 };
 
 void
-SchedServInit();
+StartSchedulerService();
+
+void
+StopSchedulerService();
 
 }
 }
diff --git a/cpp/src/server/DBWrapper.cpp b/cpp/src/server/DBWrapper.cpp
index d5ca579773ee86875235096e4c3d034a01c2d7fb..647fea598e9f6879846ce12fc2fefa998473c075 100644
--- a/cpp/src/server/DBWrapper.cpp
+++ b/cpp/src/server/DBWrapper.cpp
@@ -17,6 +17,10 @@ namespace milvus {
 namespace server {
 
 DBWrapper::DBWrapper() {
+
+}
+
+ServerError DBWrapper::StartService() {
     //db config
     zilliz::milvus::engine::Options opt;
     ConfigNode& db_config = ServerConfig::GetInstance().GetConfig(CONFIG_DB);
@@ -91,7 +95,9 @@ DBWrapper::DBWrapper() {
     //create db instance
     std::string msg = opt.meta.path;
     try {
-        zilliz::milvus::engine::DB::Open(opt, &db_);
+        engine::DB* db = nullptr;
+        zilliz::milvus::engine::DB::Open(opt, &db);
+        db_.reset(db);
     } catch(std::exception& ex) {
         msg = ex.what();
     }
@@ -100,10 +106,18 @@ DBWrapper::DBWrapper() {
         std::cout << "ERROR! Failed to open database: " << msg << std::endl;
         kill(0, SIGUSR1);
     }
+
+    db_->Start();
+
+    return SERVER_SUCCESS;
 }
 
-DBWrapper::~DBWrapper() {
-    delete db_;
+ServerError DBWrapper::StopService() {
+    if(db_) {
+        db_->Stop();
+    }
+
+    return SERVER_SUCCESS;
 }
 
 }
diff --git a/cpp/src/server/DBWrapper.h b/cpp/src/server/DBWrapper.h
index fdde4b157cfbaa71aa093966282acf8ae91d5e4a..8b25dc0d28291499de46aa89c193220a8d0a679d 100644
--- a/cpp/src/server/DBWrapper.h
+++ b/cpp/src/server/DBWrapper.h
@@ -5,8 +5,11 @@
  ******************************************************************************/
 #pragma once
 
+#include "utils/Error.h"
 #include "db/DB.h"
 
+#include <memory>
+
 namespace zilliz {
 namespace milvus {
 namespace server {
@@ -14,18 +17,27 @@ namespace server {
 class DBWrapper {
 private:
     DBWrapper();
-    ~DBWrapper();
+    ~DBWrapper() = default;
 
 public:
-    static zilliz::milvus::engine::DB* DB() {
-        static DBWrapper db_wrapper;
-        return db_wrapper.db();
+    static DBWrapper& GetInstance() {
+        static DBWrapper wrapper;
+        return wrapper;
+    }
+
+    static std::shared_ptr<engine::DB> DB() {
+        return GetInstance().EngineDB();
     }
 
-    zilliz::milvus::engine::DB* db() { return db_; }
+    ServerError StartService();
+    ServerError StopService();
+
+    std::shared_ptr<engine::DB> EngineDB() {
+        return db_;
+    }
 
 private:
-    zilliz::milvus::engine::DB* db_ = nullptr;
+    std::shared_ptr<engine::DB> db_;
 };
 
 }
diff --git a/cpp/src/server/Server.cpp b/cpp/src/server/Server.cpp
index 5c0229e319adc31edc2b0982de443f22639317ae..2df42791309f4b842a41af978441b769d3e1ba59 100644
--- a/cpp/src/server/Server.cpp
+++ b/cpp/src/server/Server.cpp
@@ -21,6 +21,7 @@
 #include <src/scheduler/SchedInst.h>
 
 #include "metrics/Metrics.h"
+#include "DBWrapper.h"
 
 namespace zilliz {
 namespace milvus {
@@ -158,7 +159,7 @@ Server::Start() {
             signal(SIGTERM, SignalUtil::HandleSignal);
             server::Metrics::GetInstance().Init();
             server::SystemInfo::GetInstance().Init();
-            engine::SchedServInit();
+
             std::cout << "Milvus server start successfully." << std::endl;
             StartService();
 
@@ -221,12 +222,16 @@ Server::LoadConfig() {
 
 void
 Server::StartService() {
+    engine::StartSchedulerService();
+    DBWrapper::GetInstance().StartService();
     grpc::GrpcMilvusServer::StartService();
 }
 
 void
 Server::StopService() {
     grpc::GrpcMilvusServer::StopService();
+    DBWrapper::GetInstance().StopService();
+    engine::StopSchedulerService();
 }
 
 }
diff --git a/cpp/src/server/grpc_impl/GrpcMilvusServer.cpp b/cpp/src/server/grpc_impl/GrpcMilvusServer.cpp
index baf9116169b08f3445ad2b93019d0dea27b60b4b..737f3dab95d72ce5340f2446c4c26044b8990dfe 100644
--- a/cpp/src/server/grpc_impl/GrpcMilvusServer.cpp
+++ b/cpp/src/server/grpc_impl/GrpcMilvusServer.cpp
@@ -49,8 +49,6 @@ GrpcMilvusServer::StartService() {
 
     faiss::distance_compute_blas_threshold = engine_config.GetInt32Value(CONFIG_DCBT, 20);
 
-    DBWrapper::DB();//initialize db
-
     std::string server_address(address + ":" + std::to_string(port));
 
     ::grpc::ServerBuilder builder;
diff --git a/cpp/src/server/grpc_impl/GrpcRequestScheduler.cpp b/cpp/src/server/grpc_impl/GrpcRequestScheduler.cpp
index 637b4c3b34154fd9c7307c2cf5653ad188f97be2..6f1a42b641b480c684816f5893390efa11de85eb 100644
--- a/cpp/src/server/grpc_impl/GrpcRequestScheduler.cpp
+++ b/cpp/src/server/grpc_impl/GrpcRequestScheduler.cpp
@@ -66,16 +66,18 @@ GrpcBaseTask::~GrpcBaseTask() {
     WaitToFinish();
 }
 
-ServerError
-GrpcBaseTask::Execute() {
+ServerError GrpcBaseTask::Execute() {
     error_code_ = OnExecute();
+    Done();
+    return error_code_;
+}
+
+void GrpcBaseTask::Done() {
     done_ = true;
     finish_cond_.notify_all();
-    return error_code_;
 }
 
-ServerError
-GrpcBaseTask::SetError(ServerError error_code, const std::string &error_msg) {
+ServerError GrpcBaseTask::SetError(ServerError error_code, const std::string &error_msg) {
     error_code_ = error_code;
     error_msg_ = error_msg;
 
@@ -83,8 +85,7 @@ GrpcBaseTask::SetError(ServerError error_code, const std::string &error_msg) {
     return error_code_;
 }
 
-ServerError
-GrpcBaseTask::WaitToFinish() {
+ServerError GrpcBaseTask::WaitToFinish() {
     std::unique_lock<std::mutex> lock(finish_mtx_);
     finish_cond_.wait(lock, [this] { return done_; });
 
@@ -101,8 +102,7 @@ GrpcRequestScheduler::~GrpcRequestScheduler() {
     Stop();
 }
 
-void
-GrpcRequestScheduler::ExecTask(BaseTaskPtr &task_ptr, ::milvus::grpc::Status *grpc_status) {
+void GrpcRequestScheduler::ExecTask(BaseTaskPtr &task_ptr, ::milvus::grpc::Status *grpc_status) {
     if (task_ptr == nullptr) {
         return;
     }
@@ -120,8 +120,7 @@ GrpcRequestScheduler::ExecTask(BaseTaskPtr &task_ptr, ::milvus::grpc::Status *gr
     }
 }
 
-void
-GrpcRequestScheduler::Start() {
+void GrpcRequestScheduler::Start() {
     if (!stopped_) {
         return;
     }
@@ -129,8 +128,7 @@ GrpcRequestScheduler::Start() {
     stopped_ = false;
 }
 
-void
-GrpcRequestScheduler::Stop() {
+void GrpcRequestScheduler::Stop() {
     if (stopped_) {
         return;
     }
@@ -155,8 +153,7 @@ GrpcRequestScheduler::Stop() {
     SERVER_LOG_INFO << "Scheduler stopped";
 }
 
-ServerError
-GrpcRequestScheduler::ExecuteTask(const BaseTaskPtr &task_ptr) {
+ServerError GrpcRequestScheduler::ExecuteTask(const BaseTaskPtr &task_ptr) {
     if (task_ptr == nullptr) {
         return SERVER_NULL_POINTER;
     }
@@ -174,33 +171,31 @@ GrpcRequestScheduler::ExecuteTask(const BaseTaskPtr &task_ptr) {
     return task_ptr->WaitToFinish();//sync execution
 }
 
-namespace {
-    void TakeTaskToExecute(TaskQueuePtr task_queue) {
-        if (task_queue == nullptr) {
-            return;
-        }
 
-        while (true) {
-            BaseTaskPtr task = task_queue->Take();
-            if (task == nullptr) {
-                SERVER_LOG_ERROR << "Take null from task queue, stop thread";
-                break;//stop the thread
-            }
+void GrpcRequestScheduler::TakeTaskToExecute(TaskQueuePtr task_queue) {
+    if (task_queue == nullptr) {
+        return;
+    }
+
+    while (true) {
+        BaseTaskPtr task = task_queue->Take();
+        if (task == nullptr) {
+            SERVER_LOG_ERROR << "Take null from task queue, stop thread";
+            break;//stop the thread
+        }
 
-            try {
-                ServerError err = task->Execute();
-                if (err != SERVER_SUCCESS) {
-                    SERVER_LOG_ERROR << "Task failed with code: " << err;
-                }
-            } catch (std::exception &ex) {
-                SERVER_LOG_ERROR << "Task failed to execute: " << ex.what();
+        try {
+            ServerError err = task->Execute();
+            if (err != SERVER_SUCCESS) {
+                SERVER_LOG_ERROR << "Task failed with code: " << err;
             }
+        } catch (std::exception &ex) {
+            SERVER_LOG_ERROR << "Task failed to execute: " << ex.what();
         }
     }
 }
 
-ServerError
-GrpcRequestScheduler::PutTaskToQueue(const BaseTaskPtr &task_ptr) {
+ServerError GrpcRequestScheduler::PutTaskToQueue(const BaseTaskPtr &task_ptr) {
     std::lock_guard<std::mutex> lock(queue_mtx_);
 
     std::string group_name = task_ptr->TaskGroup();
@@ -212,7 +207,7 @@ GrpcRequestScheduler::PutTaskToQueue(const BaseTaskPtr &task_ptr) {
         task_groups_.insert(std::make_pair(group_name, queue));
 
         //start a thread
-        ThreadPtr thread = std::make_shared<std::thread>(&TakeTaskToExecute, queue);
+        ThreadPtr thread = std::make_shared<std::thread>(&GrpcRequestScheduler::TakeTaskToExecute, this, queue);
         execute_threads_.push_back(thread);
         SERVER_LOG_INFO << "Create new thread for task group: " << group_name;
     }
diff --git a/cpp/src/server/grpc_impl/GrpcRequestScheduler.h b/cpp/src/server/grpc_impl/GrpcRequestScheduler.h
index a436e8dec6ceb36bd222b52aeeab63f1d3bae5f2..96be98836c6087fa2aaa64f671b1a7dc80b1efb5 100644
--- a/cpp/src/server/grpc_impl/GrpcRequestScheduler.h
+++ b/cpp/src/server/grpc_impl/GrpcRequestScheduler.h
@@ -25,30 +25,24 @@ protected:
     virtual ~GrpcBaseTask();
 
 public:
-    ServerError
-    Execute();
+    ServerError Execute();
 
-    ServerError
-    WaitToFinish();
+    void Done();
 
-    std::string
-    TaskGroup() const { return task_group_; }
+    ServerError WaitToFinish();
 
-    ServerError
-    ErrorCode() const { return error_code_; }
+    std::string TaskGroup() const { return task_group_; }
 
-    std::string
-    ErrorMsg() const { return error_msg_; }
+    ServerError ErrorCode() const { return error_code_; }
 
-    bool
-    IsAsync() const { return async_; }
+    std::string ErrorMsg() const { return error_msg_; }
+
+    bool IsAsync() const { return async_; }
 
 protected:
-    virtual ServerError
-    OnExecute() = 0;
+    virtual ServerError OnExecute() = 0;
 
-    ServerError
-    SetError(ServerError error_code, const std::string &msg);
+    ServerError SetError(ServerError error_code, const std::string &msg);
 
 protected:
     mutable std::mutex finish_mtx_;
@@ -77,19 +71,18 @@ public:
 
     void Stop();
 
-    ServerError
-    ExecuteTask(const BaseTaskPtr &task_ptr);
+    ServerError ExecuteTask(const BaseTaskPtr &task_ptr);
 
-    static void
-    ExecTask(BaseTaskPtr &task_ptr, ::milvus::grpc::Status *grpc_status);
+    static void ExecTask(BaseTaskPtr &task_ptr, ::milvus::grpc::Status *grpc_status);
 
 protected:
     GrpcRequestScheduler();
 
     virtual ~GrpcRequestScheduler();
 
-    ServerError
-    PutTaskToQueue(const BaseTaskPtr &task_ptr);
+    void TakeTaskToExecute(TaskQueuePtr task_queue);
+
+    ServerError PutTaskToQueue(const BaseTaskPtr &task_ptr);
 
 private:
     mutable std::mutex queue_mtx_;
diff --git a/cpp/src/server/grpc_impl/GrpcRequestTask.cpp b/cpp/src/server/grpc_impl/GrpcRequestTask.cpp
index c277f11a6189fc8a639c15d749d64217fd4e96cd..1b9bc935fae454cc7c663c8366049f12ce619a18 100644
--- a/cpp/src/server/grpc_impl/GrpcRequestTask.cpp
+++ b/cpp/src/server/grpc_impl/GrpcRequestTask.cpp
@@ -93,6 +93,7 @@ namespace {
                 return;
             }
 
+            //range: [start_day, end_day)
             for (long i = 0; i < days; i++) {
                 time_t tt_day = tt_start + DAY_SECONDS * i;
                 tm tm_day;
@@ -456,21 +457,17 @@ InsertTask::OnExecute() {
             }
         }
 
+        //step 3: check table flag
         //all user provide id, or all internal id
-        uint64_t row_count = 0;
-        DBWrapper::DB()->GetTableRowCount(table_info.table_id_, row_count);
-        bool empty_table = (row_count == 0);
         bool user_provide_ids = !insert_param_->row_id_array().empty();
-        if(!empty_table) {
-            //user already provided id before, all insert action require user id
-            if(engine::utils::UserDefinedId(table_info.flag_) && !user_provide_ids) {
-                return SetError(SERVER_INVALID_ARGUMENT, "Table vector ids are user defined, please provide id for this batch");
-            }
+        //user already provided id before, all insert action require user id
+        if((table_info.flag_ & engine::meta::FLAG_MASK_HAS_USERID) && !user_provide_ids) {
+            return SetError(SERVER_INVALID_ARGUMENT, "Table vector ids are user defined, please provide id for this batch");
+        }
 
-            //user didn't provided id before, no need to provide user id
-            if(!engine::utils::UserDefinedId(table_info.flag_) && user_provide_ids) {
-                return SetError(SERVER_INVALID_ARGUMENT, "Table vector ids are auto generated, no need to provide id for this batch");
-            }
+        //user didn't provided id before, no need to provide user id
+        if((table_info.flag_ & engine::meta::FLAG_MASK_NO_USERID) && user_provide_ids) {
+            return SetError(SERVER_INVALID_ARGUMENT, "Table vector ids are auto generated, no need to provide id for this batch");
         }
 
         rc.RecordSection("check validation");
@@ -481,7 +478,7 @@ InsertTask::OnExecute() {
         ProfilerStart(fname.c_str());
 #endif
 
-        //step 3: prepare float data
+        //step 4: prepare float data
         std::vector<float> vec_f(insert_param_->row_record_array_size() * table_info.dimension_, 0);
 
         // TODO: change to one dimension array in protobuf or use multiple-thread to copy the data
@@ -504,7 +501,7 @@ InsertTask::OnExecute() {
 
         rc.ElapseFromBegin("prepare vectors data");
 
-        //step 4: insert vectors
+        //step 5: insert vectors
         auto vec_count = (uint64_t) insert_param_->row_record_array_size();
         std::vector<int64_t> vec_ids(insert_param_->row_id_array_size(), 0);
         if(!insert_param_->row_id_array().empty()) {
@@ -529,11 +526,10 @@ InsertTask::OnExecute() {
             return SetError(SERVER_ILLEGAL_VECTOR_ID, msg);
         }
 
-        //step 5: update table flag
-        if(empty_table && user_provide_ids) {
-            stat = DBWrapper::DB()->UpdateTableFlag(insert_param_->table_name(),
-                                                    table_info.flag_ | engine::meta::FLAG_MASK_USERID);
-        }
+        //step 6: update table flag
+        user_provide_ids ? table_info.flag_ |= engine::meta::FLAG_MASK_HAS_USERID
+                : table_info.flag_ |= engine::meta::FLAG_MASK_NO_USERID;
+        stat = DBWrapper::DB()->UpdateTableFlag(insert_param_->table_name(), table_info.flag_);
 
 #ifdef MILVUS_ENABLE_PROFILING
         ProfilerStop();
diff --git a/cpp/src/wrapper/knowhere/vec_impl.cpp b/cpp/src/wrapper/knowhere/vec_impl.cpp
index b0fb4c07990b8d106a79a235a4bed819fc032b51..0b9855c639f973acac5e5187560abba8195760e4 100644
--- a/cpp/src/wrapper/knowhere/vec_impl.cpp
+++ b/cpp/src/wrapper/knowhere/vec_impl.cpp
@@ -241,8 +241,9 @@ server::KnowhereError IVFMixIndex::BuildAll(const long &nb,
         index_->Add(dataset, cfg);
 
         if (auto device_index = std::dynamic_pointer_cast<GPUIVF>(index_)) {
-            auto host_index = device_index->Copy_index_gpu_to_cpu();
+            auto host_index = device_index->CopyGpuToCpu(Config());
             index_ = host_index;
+            type = TransferToCpuIndexType(type);
         } else {
             WRAPPER_LOG_ERROR << "Build IVFMIXIndex Failed";
         }
diff --git a/cpp/src/wrapper/knowhere/vec_index.cpp b/cpp/src/wrapper/knowhere/vec_index.cpp
index c31c5261dabedf1054d0e8279b33fe4f3dcefbd7..9ac0d8b3ad8e14d925081cf91a540ac56a5640f0 100644
--- a/cpp/src/wrapper/knowhere/vec_index.cpp
+++ b/cpp/src/wrapper/knowhere/vec_index.cpp
@@ -106,6 +106,10 @@ VecIndexPtr GetVecIndexFactory(const IndexType &type) {
             index = std::make_shared<zilliz::knowhere::GPUIVFSQ>(0);
             return std::make_shared<IVFMixIndex>(index, IndexType::FAISS_IVFSQ8_MIX);
         }
+        case IndexType::FAISS_IVFSQ8: {
+            index = std::make_shared<zilliz::knowhere::IVFSQ>();
+            break;
+        }
         case IndexType::NSG_MIX: { // TODO(linxj): bug.
             index = std::make_shared<zilliz::knowhere::NSG>(0);
             break;
@@ -194,10 +198,10 @@ server::KnowhereError write_index(VecIndexPtr index, const std::string &location
 // TODO(linxj): redo here.
 void AutoGenParams(const IndexType &type, const long &size, zilliz::knowhere::Config &cfg) {
     auto nlist = cfg.get_with_default("nlist", 0);
-    if (size <= TYPICAL_COUNT/16384 + 1) {
+    if (size <= TYPICAL_COUNT / 16384 + 1) {
         //handle less row count, avoid nlist set to 0
         cfg["nlist"] = 1;
-    } else if (int(size/TYPICAL_COUNT) * nlist == 0) {
+    } else if (int(size / TYPICAL_COUNT) * nlist == 0) {
         //calculate a proper nlist if nlist not specified or size less than TYPICAL_COUNT
         cfg["nlist"] = int(size / TYPICAL_COUNT * 16384);
     }
@@ -225,6 +229,20 @@ void AutoGenParams(const IndexType &type, const long &size, zilliz::knowhere::Co
     }
 }
 
+IndexType TransferToCpuIndexType(const IndexType &type) {
+    switch (type) {
+        case IndexType::FAISS_IVFFLAT_MIX: {
+            return IndexType::FAISS_IVFFLAT_CPU;
+        }
+        case IndexType::FAISS_IVFSQ8_MIX: {
+            return IndexType::FAISS_IVFSQ8;
+        }
+        default: {
+            return IndexType::INVALID;
+        }
+    }
+}
+
 }
 }
 }
diff --git a/cpp/src/wrapper/knowhere/vec_index.h b/cpp/src/wrapper/knowhere/vec_index.h
index 19f0c6d36051cb801bd39344591bcfb17bc7da96..1c45ce89fc78defcbb9390b3c8afb4446b2870b2 100644
--- a/cpp/src/wrapper/knowhere/vec_index.h
+++ b/cpp/src/wrapper/knowhere/vec_index.h
@@ -32,6 +32,7 @@ enum class IndexType {
     FAISS_IVFPQ_GPU,
     SPTAG_KDT_RNT_CPU,
     FAISS_IVFSQ8_MIX,
+    FAISS_IVFSQ8,
     NSG_MIX,
 };
 
@@ -88,6 +89,8 @@ extern VecIndexPtr LoadVecIndex(const IndexType &index_type, const zilliz::knowh
 
 extern void AutoGenParams(const IndexType& type, const long& size, Config& cfg);
 
+extern IndexType TransferToCpuIndexType(const IndexType& type);
+
 }
 }
 }
diff --git a/cpp/unittest/db/db_tests.cpp b/cpp/unittest/db/db_tests.cpp
index 500186a0206f94b162569383abcd9f7406e06399..f37896df33db7fb822fd9f649caa1a51fd89438a 100644
--- a/cpp/unittest/db/db_tests.cpp
+++ b/cpp/unittest/db/db_tests.cpp
@@ -293,18 +293,15 @@ TEST_F(DBTest, PRELOADTABLE_TEST) {
     ASSERT_STATS(stat);
     ASSERT_EQ(table_info_get.dimension_, TABLE_DIM);
 
-    engine::IDNumbers vector_ids;
-    engine::IDNumbers target_ids;
-
-    int64_t nb = 100000;
+    int64_t nb = VECTOR_COUNT;
     std::vector<float> xb;
     BuildVectors(nb, xb);
 
     int loop = 5;
-
     for (auto i=0; i<loop; ++i) {
-        db_->InsertVectors(TABLE_NAME, nb, xb.data(), target_ids);
-        ASSERT_EQ(target_ids.size(), nb);
+        engine::IDNumbers vector_ids;
+        db_->InsertVectors(TABLE_NAME, nb, xb.data(), vector_ids);
+        ASSERT_EQ(vector_ids.size(), nb);
     }
 
     engine::TableIndex index;
@@ -342,9 +339,6 @@ TEST_F(DBTest2, ARHIVE_DISK_CHECK) {
     ASSERT_STATS(stat);
     ASSERT_EQ(table_info_get.dimension_, TABLE_DIM);
 
-    engine::IDNumbers vector_ids;
-    engine::IDNumbers target_ids;
-
     uint64_t size;
     db_->Size(size);
 
@@ -354,6 +348,7 @@ TEST_F(DBTest2, ARHIVE_DISK_CHECK) {
 
     int loop = INSERT_LOOP;
     for (auto i=0; i<loop; ++i) {
+        engine::IDNumbers vector_ids;
         db_->InsertVectors(TABLE_NAME, nb, xb.data(), vector_ids);
         std::this_thread::sleep_for(std::chrono::microseconds(1));
     }
@@ -378,20 +373,17 @@ TEST_F(DBTest2, DELETE_TEST) {
     db_->HasTable(TABLE_NAME, has_table);
     ASSERT_TRUE(has_table);
 
-    engine::IDNumbers vector_ids;
-
     uint64_t size;
     db_->Size(size);
 
-    int64_t nb = INSERT_LOOP;
+    int64_t nb = VECTOR_COUNT;
     std::vector<float> xb;
     BuildVectors(nb, xb);
 
-    int loop = 20;
-    for (auto i=0; i<loop; ++i) {
-        db_->InsertVectors(TABLE_NAME, nb, xb.data(), vector_ids);
-        std::this_thread::sleep_for(std::chrono::microseconds(1));
-    }
+    engine::IDNumbers vector_ids;
+    stat = db_->InsertVectors(TABLE_NAME, nb, xb.data(), vector_ids);
+    engine::TableIndex index;
+    stat = db_->CreateIndex(TABLE_NAME, index);
 
     std::vector<engine::meta::DateT> dates;
     stat = db_->DeleteTable(TABLE_NAME, dates);
@@ -420,25 +412,31 @@ TEST_F(DBTest2, DELETE_BY_RANGE_TEST) {
     db_->HasTable(TABLE_NAME, has_table);
     ASSERT_TRUE(has_table);
 
-    engine::IDNumbers vector_ids;
-
     uint64_t size;
     db_->Size(size);
+    ASSERT_EQ(size, 0UL);
 
-    int64_t nb = INSERT_LOOP;
+    int64_t nb = VECTOR_COUNT;
     std::vector<float> xb;
     BuildVectors(nb, xb);
 
-    int loop = 20;
-    for (auto i=0; i<loop; ++i) {
-        db_->InsertVectors(TABLE_NAME, nb, xb.data(), vector_ids);
-        std::this_thread::sleep_for(std::chrono::microseconds(1));
-    }
+    engine::IDNumbers vector_ids;
+    stat = db_->InsertVectors(TABLE_NAME, nb, xb.data(), vector_ids);
+    engine::TableIndex index;
+    stat = db_->CreateIndex(TABLE_NAME, index);
+
+    db_->Size(size);
+    ASSERT_NE(size, 0UL);
 
     std::vector<engine::meta::DateT> dates;
-    std::string start_value = CurrentTmDate(-3);
-    std::string end_value = CurrentTmDate(-2);
+    std::string start_value = CurrentTmDate();
+    std::string end_value = CurrentTmDate(1);
     ConvertTimeRangeToDBDates(start_value, end_value, dates);
 
-    db_->DeleteTable(TABLE_NAME, dates);
+    stat = db_->DeleteTable(TABLE_NAME, dates);
+    ASSERT_STATS(stat);
+
+    uint64_t row_count = 0;
+    db_->GetTableRowCount(TABLE_NAME, row_count);
+    ASSERT_EQ(row_count, 0UL);
 }
\ No newline at end of file
diff --git a/cpp/unittest/db/meta_tests.cpp b/cpp/unittest/db/meta_tests.cpp
index fa28a74eab4a831fd17214a2a8acf93c822c1806..2baad61ca46c26d130a31a006b1b3346d29a1099 100644
--- a/cpp/unittest/db/meta_tests.cpp
+++ b/cpp/unittest/db/meta_tests.cpp
@@ -74,21 +74,21 @@ TEST_F(MetaTest, TABLE_FILE_TEST) {
     ASSERT_EQ(table_file.file_type_, new_file_type);
 
     meta::DatesT dates;
-    dates.push_back(meta::Meta::GetDate());
+    dates.push_back(utils::GetDate());
     status = impl_->DropPartitionsByDates(table_file.table_id_, dates);
-    ASSERT_FALSE(status.ok());
+    ASSERT_TRUE(status.ok());
 
     dates.clear();
     for (auto i=2; i < 10; ++i) {
-        dates.push_back(meta::Meta::GetDateWithDelta(-1*i));
+        dates.push_back(utils::GetDateWithDelta(-1*i));
     }
     status = impl_->DropPartitionsByDates(table_file.table_id_, dates);
     ASSERT_TRUE(status.ok());
 
-    table_file.date_ = meta::Meta::GetDateWithDelta(-2);
+    table_file.date_ = utils::GetDateWithDelta(-2);
     status = impl_->UpdateTableFile(table_file);
     ASSERT_TRUE(status.ok());
-    ASSERT_EQ(table_file.date_, meta::Meta::GetDateWithDelta(-2));
+    ASSERT_EQ(table_file.date_, utils::GetDateWithDelta(-2));
     ASSERT_FALSE(table_file.file_type_ == meta::TableFileSchema::TO_DELETE);
 
     dates.clear();
diff --git a/cpp/unittest/db/misc_test.cpp b/cpp/unittest/db/misc_test.cpp
index 608a5ca175f3b6b1785e0d552a30312aaf7a57da..a948d1f4d93b52dc969d76c8d926ef17dcf8b071 100644
--- a/cpp/unittest/db/misc_test.cpp
+++ b/cpp/unittest/db/misc_test.cpp
@@ -105,7 +105,7 @@ TEST(DBMiscTest, META_TEST) {
     time_t tt;
     time( &tt );
     int delta = 10;
-    engine::meta::DateT dt = impl.GetDate(tt, delta);
+    engine::meta::DateT dt = engine::utils::GetDate(tt, delta);
     ASSERT_GT(dt, 0);
 }
 
diff --git a/cpp/unittest/db/mysql_meta_test.cpp b/cpp/unittest/db/mysql_meta_test.cpp
index 46b831d3ab4cd9aa0b4231bc5a6ff8273b85cabd..2ad842a2236aba947f5d0d5ea2a349dc73ec8e98 100644
--- a/cpp/unittest/db/mysql_meta_test.cpp
+++ b/cpp/unittest/db/mysql_meta_test.cpp
@@ -90,7 +90,7 @@ TEST_F(DISABLED_MySQLTest, TABLE_FILE_TEST) {
     ASSERT_EQ(table_file.file_type_, meta::TableFileSchema::NEW);
 
     meta::DatesT dates;
-    dates.push_back(meta::Meta::GetDate());
+    dates.push_back(utils::GetDate());
     status = impl.DropPartitionsByDates(table_file.table_id_, dates);
     ASSERT_FALSE(status.ok());
 
@@ -110,15 +110,15 @@ TEST_F(DISABLED_MySQLTest, TABLE_FILE_TEST) {
 
     dates.clear();
     for (auto i=2; i < 10; ++i) {
-        dates.push_back(meta::Meta::GetDateWithDelta(-1*i));
+        dates.push_back(utils::GetDateWithDelta(-1*i));
     }
     status = impl.DropPartitionsByDates(table_file.table_id_, dates);
     ASSERT_TRUE(status.ok());
 
-    table_file.date_ = meta::Meta::GetDateWithDelta(-2);
+    table_file.date_ = utils::GetDateWithDelta(-2);
     status = impl.UpdateTableFile(table_file);
     ASSERT_TRUE(status.ok());
-    ASSERT_EQ(table_file.date_, meta::Meta::GetDateWithDelta(-2));
+    ASSERT_EQ(table_file.date_, utils::GetDateWithDelta(-2));
     ASSERT_FALSE(table_file.file_type_ == meta::TableFileSchema::TO_DELETE);
 
     dates.clear();
diff --git a/cpp/unittest/knowhere/knowhere_test.cpp b/cpp/unittest/knowhere/knowhere_test.cpp
index abe7c84d4e74ca1b609987d81976b3809a33fd99..0b9e6717e11b164ff7ea8704feeed18e4e11ccaa 100644
--- a/cpp/unittest/knowhere/knowhere_test.cpp
+++ b/cpp/unittest/knowhere/knowhere_test.cpp
@@ -8,23 +8,29 @@
 #include <easylogging++.h>
 
 #include <wrapper/knowhere/vec_index.h>
+#include "knowhere/index/vector_index/gpu_ivf.h"
 
 #include "utils.h"
 
 INITIALIZE_EASYLOGGINGPP
 
 using namespace zilliz::milvus::engine;
-using namespace zilliz::knowhere;
+//using namespace zilliz::knowhere;
 
 using ::testing::TestWithParam;
 using ::testing::Values;
 using ::testing::Combine;
 
+constexpr int64_t DIM = 512;
+constexpr int64_t NB = 1000000;
 
 class KnowhereWrapperTest
     : public TestWithParam<::std::tuple<IndexType, std::string, int, int, int, int, Config, Config>> {
  protected:
     void SetUp() override {
+        zilliz::knowhere::FaissGpuResourceMgr::GetInstance().InitDevice(0);
+        zilliz::knowhere::FaissGpuResourceMgr::GetInstance().InitDevice(1);
+
         std::string generator_type;
         std::tie(index_type, generator_type, dim, nb, nq, k, train_cfg, search_cfg) = GetParam();
 
@@ -66,8 +72,8 @@ class KnowhereWrapperTest
     Config train_cfg;
     Config search_cfg;
 
-    int dim = 64;
-    int nb = 10000;
+    int dim = DIM;
+    int nb = NB;
     int nq = 10;
     int k = 10;
     std::vector<float> xb;
@@ -94,27 +100,27 @@ INSTANTIATE_TEST_CASE_P(WrapperParam, KnowhereWrapperTest,
                             //                Config::object{{"nlist", 100}, {"dim", 64}},
                             //                Config::object{{"dim", 64}, {"k", 10}, {"nprobe", 40}}
                             //),
-                            std::make_tuple(IndexType::FAISS_IVFFLAT_MIX, "Default",
-                                            64, 100000, 10, 10,
-                                            Config::object{{"nlist", 1000}, {"dim", 64}, {"metric_type", "L2"}},
-                                            Config::object{{"dim", 64}, {"k", 10}, {"nprobe", 5}}
-                            ),
-                            std::make_tuple(IndexType::FAISS_IDMAP, "Default",
-                                            64, 100000, 10, 10,
-                                            Config::object{{"dim", 64}, {"metric_type", "L2"}},
-                                            Config::object{{"dim", 64}, {"k", 10}}
-                            ),
+//                            std::make_tuple(IndexType::FAISS_IVFFLAT_MIX, "Default",
+//                                            64, 100000, 10, 10,
+//                                            Config::object{{"nlist", 1000}, {"dim", 64}, {"metric_type", "L2"}},
+//                                            Config::object{{"dim", 64}, {"k", 10}, {"nprobe", 5}}
+//                            ),
+//                            std::make_tuple(IndexType::FAISS_IDMAP, "Default",
+//                                            64, 100000, 10, 10,
+//                                            Config::object{{"dim", 64}, {"metric_type", "L2"}},
+//                                            Config::object{{"dim", 64}, {"k", 10}}
+//                            ),
                             std::make_tuple(IndexType::FAISS_IVFSQ8_MIX, "Default",
-                                            64, 100000, 10, 10,
-                                            Config::object{{"dim", 64}, {"nlist", 1000}, {"nbits", 8}, {"metric_type", "L2"}},
-                                            Config::object{{"dim", 64}, {"k", 10}, {"nprobe", 5}}
-                            ),
-                            std::make_tuple(IndexType::NSG_MIX, "Default",
-                                            128, 250000, 10, 10,
-                                            Config::object{{"dim", 128}, {"nlist", 8192}, {"nprobe", 16}, {"metric_type", "L2"},
-                                                           {"knng", 200}, {"search_length", 40}, {"out_degree", 60}, {"candidate_pool_size", 200}},
-                                            Config::object{{"k", 10}, {"search_length", 20}}
+                                            DIM, NB, 10, 10,
+                                            Config::object{{"dim", DIM}, {"nlist", 1000}, {"nbits", 8}, {"metric_type", "L2"}},
+                                            Config::object{{"dim", DIM}, {"k", 10}, {"nprobe", 5}}
                             )
+//                            std::make_tuple(IndexType::NSG_MIX, "Default",
+//                                            128, 250000, 10, 10,
+//                                            Config::object{{"dim", 128}, {"nlist", 8192}, {"nprobe", 16}, {"metric_type", "L2"},
+//                                                           {"knng", 200}, {"search_length", 40}, {"out_degree", 60}, {"candidate_pool_size", 200}},
+//                                            Config::object{{"k", 10}, {"search_length", 20}}
+//                            )
                             //std::make_tuple(IndexType::SPTAG_KDT_RNT_CPU, "Default",
                             //                64, 10000, 10, 10,
                             //                Config::object{{"TPTNumber", 1}, {"dim", 64}},
@@ -135,6 +141,31 @@ TEST_P(KnowhereWrapperTest, base_test) {
     AssertResult(res_ids, res_dis);
 }
 
+TEST_P(KnowhereWrapperTest, to_gpu_test) {
+    EXPECT_EQ(index_->GetType(), index_type);
+
+    auto elems = nq * k;
+    std::vector<int64_t> res_ids(elems);
+    std::vector<float> res_dis(elems);
+
+    index_->BuildAll(nb, xb.data(), ids.data(), train_cfg);
+    index_->Search(nq, xq.data(), res_dis.data(), res_ids.data(), search_cfg);
+    AssertResult(res_ids, res_dis);
+    {
+        index_->CopyToGpu(1);
+    }
+
+    std::string file_location = "/tmp/whatever";
+    write_index(index_, file_location);
+    auto new_index = read_index(file_location);
+
+    auto dev_idx = new_index->CopyToGpu(1);
+    for (int i = 0; i < 10000; ++i) {
+        dev_idx->Search(nq, xq.data(), res_dis.data(), res_ids.data(), search_cfg);
+    }
+    AssertResult(res_ids, res_dis);
+}
+
 TEST_P(KnowhereWrapperTest, serialize) {
     EXPECT_EQ(index_->GetType(), index_type);