diff --git a/include/ylt/metric/counter.hpp b/include/ylt/metric/counter.hpp
index 95a2f3e41..246b8ed47 100644
--- a/include/ylt/metric/counter.hpp
+++ b/include/ylt/metric/counter.hpp
@@ -210,14 +210,15 @@ class basic_dynamic_counter : public dynamic_metric {
       return;
     }
 
-    std::lock_guard lock(mtx_);
+    std::unique_lock lock(mtx_);
     if (value_map_.size() > ylt_label_capacity) {
       return;
     }
     auto [it, r] = value_map_.try_emplace(
         labels_value, thread_local_value<value_type>(dupli_count_));
+    lock.unlock();
     if (r) {
-      g_user_metric_label_count.local_value()++;
+      g_user_metric_label_count->local_value()++;
       if (ylt_label_max_age.count()) {
         it->second.set_created_time(std::chrono::system_clock::now());
       }
@@ -227,14 +228,15 @@ class basic_dynamic_counter : public dynamic_metric {
 
   value_type update(const std::array<std::string, N> &labels_value,
                     value_type value) {
-    std::lock_guard lock(mtx_);
+    std::unique_lock lock(mtx_);
     if (value_map_.size() > ylt_label_capacity) {
       return value_type{};
     }
     auto [it, r] = value_map_.try_emplace(
         labels_value, thread_local_value<value_type>(dupli_count_));
+    lock.unlock();
     if (r) {
-      g_user_metric_label_count.local_value()++;
+      g_user_metric_label_count->local_value()++;
       if (ylt_label_max_age.count()) {
         it->second.set_created_time(std::chrono::system_clock::now());
       }
diff --git a/include/ylt/metric/gauge.hpp b/include/ylt/metric/gauge.hpp
index cd2ba69a4..c68d46de6 100644
--- a/include/ylt/metric/gauge.hpp
+++ b/include/ylt/metric/gauge.hpp
@@ -66,14 +66,15 @@ class basic_dynamic_gauge : public basic_dynamic_counter<value_type, N> {
       return;
     }
 
-    std::lock_guard lock(mtx_);
+    std::unique_lock lock(mtx_);
     if (value_map_.size() > ylt_label_capacity) {
       return;
     }
     auto [it, r] = value_map_.try_emplace(
         labels_value, thread_local_value<value_type>(dupli_count_));
+    lock.unlock();
     if (r) {
-      g_user_metric_label_count.local_value()++;
+      g_user_metric_label_count->local_value()++;
       if (ylt_label_max_age.count()) {
         it->second.set_created_time(std::chrono::system_clock::now());
       }
diff --git a/include/ylt/metric/metric.hpp b/include/ylt/metric/metric.hpp
index 1ee5a18eb..f37de8cab 100644
--- a/include/ylt/metric/metric.hpp
+++ b/include/ylt/metric/metric.hpp
@@ -225,7 +225,7 @@ class dynamic_metric : public metric_t {
   using metric_t::metric_t;
 };
 
-inline thread_local_value<int64_t> g_user_metric_label_count{2};
+inline auto g_user_metric_label_count = new thread_local_value<int64_t>(2);
 inline std::atomic<int64_t> g_summary_failed_count = 0;
 inline std::atomic<int64_t> g_user_metric_count = 0;
 
diff --git a/include/ylt/metric/metric_manager.hpp b/include/ylt/metric/metric_manager.hpp
index 5ae16c2dd..8a48d5f12 100644
--- a/include/ylt/metric/metric_manager.hpp
+++ b/include/ylt/metric/metric_manager.hpp
@@ -169,8 +169,8 @@ class static_metric_manager {
   static_metric_manager& operator=(static_metric_manager&&) = delete;
 
   static static_metric_manager<Tag>& instance() {
-    static static_metric_manager<Tag> inst;
-    return inst;
+    static auto* inst = new static_metric_manager<Tag>();
+    return *inst;
   }
 
   template <typename T, typename... Args>
@@ -279,8 +279,8 @@ class dynamic_metric_manager {
   dynamic_metric_manager& operator=(dynamic_metric_manager&&) = delete;
 
   static dynamic_metric_manager<Tag>& instance() {
-    static dynamic_metric_manager<Tag> inst;
-    return inst;
+    static auto* inst = new dynamic_metric_manager<Tag>();
+    return *inst;
   }
 
   template <typename T, typename... Args>
diff --git a/include/ylt/metric/system_metric.hpp b/include/ylt/metric/system_metric.hpp
index dffbab3b3..8cd305f9c 100644
--- a/include/ylt/metric/system_metric.hpp
+++ b/include/ylt/metric/system_metric.hpp
@@ -362,7 +362,7 @@ inline void stat_metric() {
   static auto user_metric_label_count =
       system_metric_manager::instance().get_metric_static<gauge_t>(
           "ylt_user_metric_labels");
-  user_metric_label_count->update(g_user_metric_label_count.value());
+  user_metric_label_count->update(g_user_metric_label_count->value());
 
   static auto ylt_summary_failed_count =
       system_metric_manager::instance().get_metric_static<gauge_t>(
@@ -379,7 +379,12 @@ inline void ylt_stat() {
   stat_metric();
 }
 
-inline void start_stat(std::shared_ptr<coro_io::period_timer> timer) {
+inline void start_stat(std::weak_ptr<coro_io::period_timer> weak) {
+  auto timer = weak.lock();
+  if (timer == nullptr) {
+    return;
+  }
+
   timer->expires_after(std::chrono::seconds(1));
   timer->async_wait([timer](std::error_code ec) {
     if (ec) {