diff --git a/CHANGELOG.md b/CHANGELOG.md
index 93021475d9226bae240e2bc5a010739f6ef7e8ba..bd6edf52f6b2b4113b7411e50be2ce8b439c99e6 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -7,6 +7,7 @@ Please mark all change in change log and use the ticket from JIRA.
 ## Bug
 - \#134 - JFrog cache error
 - \#161 - Search IVFSQHybrid crash on gpu
+- \#169 - IVF_FLAT search out of memory
 
 ## Feature
 - \#90 - The server start error messages could be improved to enhance user experience
diff --git a/core/src/db/engine/ExecutionEngineImpl.cpp b/core/src/db/engine/ExecutionEngineImpl.cpp
index e0e5c39de67fc60c320f6e8dacacb421755c6b9d..ee04191fef09a2344c3aed2998785b0eddbf52fa 100644
--- a/core/src/db/engine/ExecutionEngineImpl.cpp
+++ b/core/src/db/engine/ExecutionEngineImpl.cpp
@@ -309,30 +309,13 @@ ExecutionEngineImpl::CopyToGpu(uint64_t device_id, bool hybrid) {
         return Status::OK();
     }
 #endif
-
-    auto index = std::static_pointer_cast<VecIndex>(cache::GpuCacheMgr::GetInstance(device_id)->GetIndex(location_));
-    bool already_in_cache = (index != nullptr);
-    if (already_in_cache) {
-        index_ = index;
-    } else {
-        if (index_ == nullptr) {
-            ENGINE_LOG_ERROR << "ExecutionEngineImpl: index is null, failed to copy to gpu";
-            return Status(DB_ERROR, "index is null");
-        }
-
-        try {
-            index_ = index_->CopyToGpu(device_id);
-            ENGINE_LOG_DEBUG << "CPU to GPU" << device_id;
-        } catch (std::exception& e) {
-            ENGINE_LOG_ERROR << e.what();
-            return Status(DB_ERROR, e.what());
-        }
+    try {
+        index_ = index_->CopyToGpu(device_id);
+        ENGINE_LOG_DEBUG << "CPU to GPU" << device_id;
+    } catch (std::exception& e) {
+        ENGINE_LOG_ERROR << e.what();
+        return Status(DB_ERROR, e.what());
     }
-
-    if (!already_in_cache) {
-        GpuCache(device_id);
-    }
-
     return Status::OK();
 }