maybe no atomic on active?

include/logger.hh

@@ -34,6 +34,7 @@ class Logger {
             typename = std::enable_if_t<std::is_arithmetic_v<Metric>>>
   void add(const std::string& field, Metric metric) {
     auto locked = active.load();
+    // auto locked = active;
     auto it = locked->find(field);
     if (it == locked->end()) {
       throw configErrorMsg;
@@ -50,6 +51,7 @@ class Logger {
   std::unique_ptr<Worker> worker;
   std::shared_ptr<map_type> m1, m2;
   std::atomic<std::shared_ptr<map_type>> active;  // impl may use mutex!
+  // std::shared_ptr<map_type> active;
 };
 
 }  // namespace vptyp

src/logger.cc

@@ -62,10 +62,12 @@ void Logger::Worker::unroll() {
     return;
 
   auto tmp = parent.active.load();
+  // auto tmp = parent.active;
   auto toBeActive = tmp == parent.m1 ? parent.m2 : parent.m1;
   while (!parent.active.compare_exchange_weak(tmp, toBeActive)) {
     std::this_thread::yield();
   }
+  // parent.active = toBeActive;
 
   while (tmp.use_count() > 2) {
     std::this_thread::yield();