diff --git a/imperative/python/megengine/__init__.py b/imperative/python/megengine/__init__.py
index 320aa125df7c2131e159af89e297ba3dfc031806..d43f16b37bc858dbddffff27985d29b0fda6d810 100644
--- a/imperative/python/megengine/__init__.py
+++ b/imperative/python/megengine/__init__.py
@@ -71,6 +71,7 @@ if sys.platform == "win32":
 
     kernel32.SetErrorMode(old_error_mode)
 
+from .core._imperative_rt.core2 import close as _close
 from .core._imperative_rt.core2 import full_sync as _full_sync
 from .core._imperative_rt.core2 import sync as _sync
 from .core._imperative_rt.utils import _set_fork_exec_path_for_timed_func
@@ -90,7 +91,7 @@ _set_fork_exec_path_for_timed_func(
 _persistent_cache_impl_ins = persistent_cache.PersistentCacheOnServer()
 _persistent_cache_impl_ins.reg()
 
-atexit.register(_full_sync)
+atexit.register(_close)
 
 del _set_fork_exec_path_for_timed_func
 
diff --git a/imperative/python/src/tensor.cpp b/imperative/python/src/tensor.cpp
index 344046f87e7bfef38320996f74a51295eb5aef0a..1b16fe5619d988fa3d1634877efd16e8beb8f4c9 100644
--- a/imperative/python/src/tensor.cpp
+++ b/imperative/python/src/tensor.cpp
@@ -897,6 +897,11 @@ void init_tensor(py::module m) {
         }
     }
 
+    static constexpr auto sync_py_task_q = []{
+        py::gil_scoped_release _;
+        py_task_q.wait_all_task_finish();
+    };
+
     m.def("set_option",
           [](std::string name, size_t value){ interpreter_for_py->set_option(name, value); });
     m.def("get_option",
@@ -928,16 +933,19 @@ void init_tensor(py::module m) {
     m.def("sync",
           []() {
               interpreter_for_py->sync();
-              py_task_q.wait_all_task_finish();
-          },
-          py::call_guard<py::gil_scoped_release>());
+              sync_py_task_q();
+          });
     m.def("full_sync",
           []() {
               interpreter_for_py->sync();
               CompNode::sync_all();
-              py_task_q.wait_all_task_finish();
-          },
-          py::call_guard<py::gil_scoped_release>());
+              sync_py_task_q();
+          });
+    m.def("close",
+          []() {
+              interpreter_for_py->close();
+              sync_py_task_q();
+          });
 
     py::handle grad_key_type = GradKeyWrapper::wrap_t::type()
         .def<&GradKeyWrapper::attach>("attach")
diff --git a/imperative/python/test/unit/core/test_interpreter.py b/imperative/python/test/unit/core/test_interpreter.py
index cee94b612bf2ba3948e4694a2e6502c5b4877ed2..5481901355e0f640e61722cedb8a6c7f5af3b802 100644
--- a/imperative/python/test/unit/core/test_interpreter.py
+++ b/imperative/python/test/unit/core/test_interpreter.py
@@ -1,3 +1,6 @@
+import subprocess
+import sys
+
 import numpy as np
 import pytest
 
@@ -76,3 +79,14 @@ def test_swap_drop_basic():
     z.numpy()
     _set_swap_flag(False)
     _set_drop_flag(False)
+
+
+def test_finalize():
+    prog = """
+import megengine
+with megengine.core.option("enable_host_compute", 0):
+    x = megengine.tensor(0)
+    y = x + 1
+    y.numpy()
+"""
+    subprocess.check_call([sys.executable, "-c", prog])
diff --git a/imperative/src/impl/event_pool.cpp b/imperative/src/impl/event_pool.cpp
index 4f27fa0e20de5686b8ffea4176edec3c563425e2..c6eedee5bd1d40dbc8d9f0f5f95dea5d8fc23a5c 100644
--- a/imperative/src/impl/event_pool.cpp
+++ b/imperative/src/impl/event_pool.cpp
@@ -67,6 +67,7 @@ std::shared_ptr<void> EventPool::on_comp_node_finalize() {
     for (auto&& i : m_cn2pool) {
         i.second.assert_all_freed();
     }
+    m_cn2pool.clear();
     return {};
 }
 EventPool::~EventPool() {
diff --git a/imperative/src/impl/interpreter/interpreter_impl.cpp b/imperative/src/impl/interpreter/interpreter_impl.cpp
index 50f649f138ea981b386607ee6a3c830a2254bd8c..1843c6b222bbe739b610103994f2427a68d6bb2a 100644
--- a/imperative/src/impl/interpreter/interpreter_impl.cpp
+++ b/imperative/src/impl/interpreter/interpreter_impl.cpp
@@ -33,6 +33,7 @@ Interpreter& Interpreter::inst() {
 }
 
 Handle ChannelImpl::put(const HostTensorND& value, bool no_cache) {
+    mgb_assert(check_available(), "Channel already closed");
     auto info = alloc();
     info->desc.layout = value.layout();
     info->desc.comp_node = value.comp_node();
@@ -47,6 +48,7 @@ Handle ChannelImpl::put(const HostTensorND& value, bool no_cache) {
 }
 
 Handle ChannelImpl::put(const DeviceTensorND& data) {
+    mgb_assert(check_available(), "Channel already closed");
     auto info = alloc();
     info->desc.layout = data.layout();
     info->desc.comp_node = data.comp_node();
@@ -58,6 +60,9 @@ Handle ChannelImpl::put(const DeviceTensorND& data) {
 }
 
 void ChannelImpl::del(Handle handle) {
+    if (!check_available()){
+        return;
+    }
     mgb_assert(m_valid_handle.count(handle), "invalid handle: %p", handle);
     auto* info = reinterpret_cast<TensorInfo*>(handle);
     m_valid_handle.erase(handle);
@@ -65,6 +70,7 @@ void ChannelImpl::del(Handle handle) {
 }
 
 void ChannelImpl::swap_in(Handle handle) {
+    mgb_assert(check_available(), "Channel already closed");
     if (m_worker_state.options.enable_swap) {
         mgb_assert(m_valid_handle.find(handle) != m_valid_handle.end(),
                 "invalid handle: %p", handle);
@@ -74,6 +80,7 @@ void ChannelImpl::swap_in(Handle handle) {
 }
 
 void ChannelImpl::swap_out(Handle handle) {
+    mgb_assert(check_available(), "Channel already closed");
     if (m_worker_state.options.enable_swap) {
         mgb_assert(m_valid_handle.find(handle) != m_valid_handle.end(),
                 "invalid handle: %p", handle);
@@ -83,6 +90,7 @@ void ChannelImpl::swap_out(Handle handle) {
 }
 
 void ChannelImpl::drop(Handle handle) {
+    mgb_assert(check_available(), "Channel already closed");
     if (m_worker_state.options.enable_drop) {
         mgb_assert(m_valid_handle.find(handle) != m_valid_handle.end(),
                 "invalid handle: %p", handle);
@@ -201,6 +209,7 @@ void ChannelImpl::dispatch_kernel(
 SmallVector<Handle> ChannelImpl::apply_op(
         std::shared_ptr<OpDef> op,
         const SmallVector<Handle>& inputs) {
+    mgb_assert(check_available(), "Channel already closed");
     for (auto i : inputs) {
         mgb_assert(m_valid_handle.find(i) != m_valid_handle.end(),
                 "invalid handle: %p", i);
@@ -237,6 +246,7 @@ SmallVector<Handle> ChannelImpl::apply_op(
 }
 
 HostTensorND ChannelImpl::get_value(Handle handle) {
+    mgb_assert(check_available(), "Channel already closed");
     // TODO: maybe get_value should be done on host. i.e. delete GetValue
     mgb_assert(m_valid_handle.find(handle) != m_valid_handle.end(),
                "invalid handle: %p", handle);
@@ -269,6 +279,7 @@ HostTensorND ChannelImpl::get_value(Handle handle) {
 }
 
 TensorShape ChannelImpl::get_shape(Handle handle) {
+    mgb_assert(check_available(), "Channel already closed");
     mgb_assert(m_valid_handle.find(handle) != m_valid_handle.end(),
                "invalid handle: %p", handle);
     auto info = reinterpret_cast<TensorInfo*>(handle);
@@ -296,6 +307,7 @@ TensorShape ChannelImpl::get_shape(Handle handle) {
 }
 
 DType ChannelImpl::get_dtype(Handle handle) {
+    mgb_assert(check_available(), "Channel already closed");
     mgb_assert(m_valid_handle.find(handle) != m_valid_handle.end(),
                "invalid handle: %p", handle);
     auto info = reinterpret_cast<TensorInfo*>(handle);
@@ -308,6 +320,7 @@ DType ChannelImpl::get_dtype(Handle handle) {
 }
 
 CompNode ChannelImpl::get_device(Handle handle) {
+    mgb_assert(check_available(), "Channel already closed");
     mgb_assert(m_valid_handle.find(handle) != m_valid_handle.end(),
                "invalid handle: %p", handle);
     auto info = reinterpret_cast<TensorInfo*>(handle);
@@ -320,6 +333,7 @@ CompNode ChannelImpl::get_device(Handle handle) {
 }
 
 DeviceTensorND ChannelImpl::get_dev_tensor(Handle handle) {
+    mgb_assert(check_available(), "Channel already closed");
     mgb_assert(m_valid_handle.find(handle) != m_valid_handle.end(),
                "invalid handle: %p", handle);
     auto info = reinterpret_cast<TensorInfo*>(handle);
@@ -342,6 +356,7 @@ DeviceTensorND ChannelImpl::get_dev_tensor(Handle handle) {
 }
 
 void ChannelImpl::sync() {
+    mgb_assert(check_available(), "Channel already closed");
     m_buffer.flush();
     if (m_channel_state.profiler->is_profiling()) {
         m_channel_state.profiler->record_host<SyncStartEvent>();
@@ -356,14 +371,26 @@ void ChannelImpl::sync() {
 }
 
 void ChannelImpl::close() {
+    if (!check_available()) {
+        return;
+    }
+    std::vector<Handle> valid_handles(m_valid_handle.begin(), m_valid_handle.end());
+    for (auto* handle: valid_handles) {
+        del(handle);
+    }
+    mgb_assert(m_valid_handle.empty());
+    mgb_log_debug("%ld tensor exists before channel close", (long)valid_handles.size());
     sync();
+    m_closed = true;
 }
 
 size_t ChannelImpl::get_option(std::string name) {
+    mgb_assert(check_available(), "Channel already closed");
     return m_channel_state.options.get_option(name);
 }
 
 void ChannelImpl::set_option(std::string name, size_t value) {
+    mgb_assert(check_available(), "Channel already closed");
     m_channel_state.options.set_option(name, value);
     m_buffer.enqueue(SetOption{name, value});
 }
@@ -440,9 +467,7 @@ void ChannelImpl::real_free(TensorInfo* ptr) {
     m_pool.free(ptr);
 }
 
-ChannelImpl::ChannelImpl() : m_worker(this), m_buffer(this){
-    m_channel_state.tid = std::this_thread::get_id();
-}
+ChannelImpl::ChannelImpl() : m_worker(this), m_buffer(this){}
 
 ChannelImpl::~ChannelImpl() {
     close();
@@ -562,6 +587,10 @@ void ChannelImpl::detach_users(TensorInfo* dest) {
     //dest->users.clear();
 }
 
+bool ChannelImpl::check_available() {
+    return !m_closed;
+}
+
 void ChannelImpl::sync_device_scope(CompNode device) {
     auto& prev = m_worker_state.device_scope_map[device];
     auto& current = m_worker_state.scopes;
@@ -786,9 +815,7 @@ void ChannelImpl::process_one_task(IdentifiedCommand& icmd) {
                 std::swap(profiler, m_worker_state.profiler);
                 auto records = profiler->stop();
                 auto host_map = [this](std::thread::id tid) {
-                    if (tid == m_channel_state.tid) {
-                        return "channel";
-                    } else if (tid == m_worker_state.tid) {
+                    if (tid == m_worker_state.tid) {
                         return "worker";
                     } else {
                         return "unknown";
@@ -959,6 +986,7 @@ auto ChannelImpl::CommandBuffer::find_produce(TensorInfo* dest, Range range)
 }
 
 void ChannelImpl::start_profile(std::unordered_map<std::string, int> option) {
+    mgb_assert(check_available(), "Channel already closed");
     auto profiler_option = InterpreterProfiler::Option::from_dict(option);
     auto profiler = std::make_unique<InterpreterProfiler>();
     profiler->set_option(profiler_option);
@@ -968,6 +996,7 @@ void ChannelImpl::start_profile(std::unordered_map<std::string, int> option) {
 }
 
 void ChannelImpl::stop_profile(std::string basename, std::string format) {
+    mgb_assert(check_available(), "Channel already closed");
     m_buffer.flush();
     auto profiler = std::make_unique<InterpreterProfiler>();
     std::swap(profiler, m_channel_state.profiler);
@@ -976,6 +1005,7 @@ void ChannelImpl::stop_profile(std::string basename, std::string format) {
 }
 
 void ChannelImpl::push_scope(std::string name) {
+    mgb_assert(check_available(), "Channel already closed");
     if (m_channel_state.profiler->is_profiling()) {
         m_channel_state.profiler->record_host<ChannelBeginScope>(name);
         m_channel_state.scopes.push_back(name);
@@ -984,6 +1014,7 @@ void ChannelImpl::push_scope(std::string name) {
 }
 
 void ChannelImpl::pop_scope(std::string name) {
+    mgb_assert(check_available(), "Channel already closed");
     if (m_channel_state.profiler->is_profiling()) {
         mgb_assert((!m_channel_state.scopes.empty()) && m_channel_state.scopes.back() == name, "scope name mismatch");
         m_channel_state.scopes.pop_back();
@@ -992,14 +1023,6 @@ void ChannelImpl::pop_scope(std::string name) {
     }
 }
 
-void ChannelImpl::assert_in_channel() {
-    mgb_assert(m_channel_state.tid != std::this_thread::get_id());
-}
-
-void ChannelImpl::assert_in_worker() {
-    mgb_assert(m_worker_state.tid == std::this_thread::get_id());
-}
-
 void ChannelImpl::DynamicSublinear::pin(const SmallVector<TensorInfo*>& vec) {
     for (auto i : vec) {
         i->pin();
diff --git a/imperative/src/impl/interpreter/interpreter_impl.h b/imperative/src/impl/interpreter/interpreter_impl.h
index 72136fecef1a79425018fb5aafb9f12587e2e141..0d11c1c7a2fdb57929517cbd33b3435ad05f8f91 100644
--- a/imperative/src/impl/interpreter/interpreter_impl.h
+++ b/imperative/src/impl/interpreter/interpreter_impl.h
@@ -18,6 +18,7 @@
 #include <unordered_set>
 #include <variant>
 
+#include "megbrain/comp_node.h"
 #include "megbrain/utils/mempool.h"
 #include "megbrain/imperative/interpreter.h"
 #include "megbrain/imperative/profiler.h"
@@ -102,8 +103,7 @@ private:
         const SmallVector<LogicalTensorDesc>& input_descs,
         SmallVector<Handle>* outputs);
 
-    void assert_in_channel();
-    void assert_in_worker();
+    bool check_available();
 
     void sync_device_scope(CompNode device);
 
@@ -120,6 +120,8 @@ private:
     std::exception_ptr m_worker_exc;
     std::atomic_uint64_t m_last_id = 0;
 
+    bool m_closed = false;
+
     struct WorkQueue : AsyncQueueSC<IdentifiedCommand, WorkQueue> {
         // set max_spin=0 to prevent Queue fetch task in busy wait manner.
         // this won't affect throughput when python interpreter is sending enough task,
@@ -186,7 +188,6 @@ private:
     int m_async_level = 2;
 
     struct State {
-        std::thread::id tid;
         OptionManager options;
         std::vector<std::string> scopes;
         std::unique_ptr<InterpreterProfiler> profiler;
@@ -199,6 +200,7 @@ private:
     struct ChannelState: State {};
 
     struct WorkerState: State {
+        std::thread::id tid;
         CompNode::UnorderedMap<std::vector<std::string>> device_scope_map;
     };