diff --git a/CHANGELOG.md b/CHANGELOG.md
index 060aaed1a0..957821ff4c 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -20,6 +20,7 @@ Please mark all change in change log and use the ticket from JIRA.
 - \#440 - Query API in customization still uses old version
 - \#440 - Server cannot startup with gpu_resource_config.enable=false in GPU version
 - \#458 - Index data is not compatible between 0.5 and 0.6
+- \#465 - Server hang caused by searching with nsg index
 - \#486 - gpu no usage during index building
 - \#513 - Unittest DELETE_BY_RANGE sometimes failed
 
diff --git a/core/build.sh b/core/build.sh
index 3afb5d1b37..badcc5a032 100755
--- a/core/build.sh
+++ b/core/build.sh
@@ -56,7 +56,7 @@ while getopts "p:d:t:f:ulrcgjhxzme" arg; do
     USE_JFROG_CACHE="ON"
     ;;
   x)
-    CUSTOMIZATION="OFF" # force use ori faiss
+    CUSTOMIZATION="ON"
     ;;
   g)
     GPU_VERSION="ON"
diff --git a/core/src/index/knowhere/knowhere/common/Timer.cpp b/core/src/index/knowhere/knowhere/common/Timer.cpp
index fefe1e1705..141e1ceed6 100644
--- a/core/src/index/knowhere/knowhere/common/Timer.cpp
+++ b/core/src/index/knowhere/knowhere/common/Timer.cpp
@@ -17,6 +17,7 @@
 
 #include <iostream>  // TODO(linxj): using Log instead
 
+#include "knowhere/common/Log.h"
 #include "knowhere/common/Timer.h"
 
 namespace knowhere {
@@ -51,30 +52,18 @@ TimeRecorder::PrintTimeRecord(const std::string& msg, double span) {
             std::cout << str_log << std::endl;
             break;
         }
-            // case 1: {
-            //    SERVER_LOG_DEBUG << str_log;
-            //    break;
-            //}
+        case 1: {
+            KNOWHERE_LOG_DEBUG << str_log;
+            break;
+        }
             // case 2: {
-            //    SERVER_LOG_INFO << str_log;
-            //    break;
-            //}
+            //     KNOWHERE_LOG_TRACE << str_log;
+            //     break;
+            // }
             // case 3: {
-            //    SERVER_LOG_WARNING << str_log;
-            //    break;
-            //}
-            // case 4: {
-            //    SERVER_LOG_ERROR << str_log;
-            //    break;
-            //}
-            // case 5: {
-            //    SERVER_LOG_FATAL << str_log;
-            //    break;
-            //}
-            // default: {
-            //    SERVER_LOG_INFO << str_log;
-            //    break;
-            //}
+            //     KNOWHERE_LOG_WARNING << str_log;
+            //     break;
+            // }
     }
 }
 
diff --git a/core/src/index/knowhere/knowhere/index/vector_index/nsg/NSG.cpp b/core/src/index/knowhere/knowhere/index/vector_index/nsg/NSG.cpp
index bdf538c204..b4e00e57b7 100644
--- a/core/src/index/knowhere/knowhere/index/vector_index/nsg/NSG.cpp
+++ b/core/src/index/knowhere/knowhere/index/vector_index/nsg/NSG.cpp
@@ -718,29 +718,38 @@ NsgIndex::Search(const float* query, const unsigned& nq, const unsigned& dim, co
                  int64_t* ids, SearchParams& params) {
     std::vector<std::vector<Neighbor>> resset(nq);
 
-    TimeRecorder rc("search");
-    if (nq == 1) {
+    params.search_length = k;
+    TimeRecorder rc("NsgIndex::search", 1);
+    // TODO(linxj): when to use openmp
+    if (nq <= 4) {
         GetNeighbors(query, resset[0], nsg, &params);
     } else {
-//#pragma omp parallel for schedule(dynamic, 50)
 #pragma omp parallel for
         for (unsigned int i = 0; i < nq; ++i) {
-            // TODO(linxj): when to use openmp
             auto single_query = query + i * dim;
             GetNeighbors(single_query, resset[i], nsg, &params);
         }
     }
-    rc.ElapseFromBegin("cost");
-
+    rc.RecordSection("search");
     for (unsigned int i = 0; i < nq; ++i) {
-        for (unsigned int j = 0; j < k; ++j) {
-            // ids[i * k + j] = resset[i][j].id;
-
-            // Fix(linxj): bug, reset[i][j] out of range
-            ids[i * k + j] = ids_[resset[i][j].id];
-            dist[i * k + j] = resset[i][j].distance;
+        int64_t var = resset[i].size() - k;
+        if (var >= 0) {
+            for (unsigned int j = 0; j < k; ++j) {
+                ids[i * k + j] = ids_[resset[i][j].id];
+                dist[i * k + j] = resset[i][j].distance;
+            }
+        } else {
+            for (unsigned int j = 0; j < resset[i].size(); ++j) {
+                ids[i * k + j] = ids_[resset[i][j].id];
+                dist[i * k + j] = resset[i][j].distance;
+            }
+            for (unsigned int j = resset[i].size(); j < k; ++j) {
+                ids[i * k + j] = -1;
+                dist[i * k + j] = -1;
+            }
         }
     }
+    rc.RecordSection("merge");
 
     //>> Debug: test single insert
     // int x_0 = resset[0].size();