More improvements to the async logger

include/spdlog/async_logger.h

@@ -46,9 +46,9 @@ class async_logger :public logger
 {
 public:
     template<class It>
-    async_logger(const std::string& name, const It& begin, const It& end, size_t queue_size, const log_clock::duration& shutdown_duration);
-    async_logger(const std::string& logger_name, sinks_init_list sinks, size_t queue_size, const log_clock::duration& shutdown_duration);
-    async_logger(const std::string& logger_name, sink_ptr single_sink, size_t queue_size, const log_clock::duration& shutdown_duration);
+    async_logger(const std::string& name, const It& begin, const It& end, size_t queue_size);
+    async_logger(const std::string& logger_name, sinks_init_list sinks, size_t queue_size);
+    async_logger(const std::string& logger_name, sink_ptr single_sink, size_t queue_size);
 
 
 protected:
@@ -58,7 +58,6 @@ protected:
     void _stop() override;
 
 private:
-    log_clock::duration _shutdown_duration;
     std::unique_ptr<details::async_log_helper> _async_log_helper;
 };
 }

include/spdlog/details/async_log_helper.h

@@ -115,9 +115,6 @@ public:
     //Stop logging and join the back thread
     ~async_log_helper();
     void set_formatter(formatter_ptr);
-    //Wait to remaining items (if any) in the queue to be written and shutdown
-    void shutdown(const log_clock::duration& timeout);
-
 
 
 private:
@@ -131,14 +128,16 @@ private:
     std::shared_ptr<spdlog_ex> _last_workerthread_ex;
 
 
-
-
-    // will throw last worker thread exception or if worker thread no active
+    // throw last worker thread exception or if worker thread is not active
     void throw_if_bad_worker();
 
-    // worker thread loop
+    // worker thread main loop
     void worker_loop();
 
+    //pop next message from the queue and process it
+    //return true if a message was available (queue was not empty), will set the last_pop to the pop time
+    bool process_next_msg(clock::time_point& last_pop);
+
     // guess how much to sleep if queue is empty/full using last succesful op time as hint
     static void sleep_or_yield(const clock::time_point& last_op_time);
 
@@ -146,7 +145,6 @@ private:
     // clear all remaining messages(if any), stop the _worker_thread and join it
     void join_worker();
 
-
 };
 }
 }
@@ -155,7 +153,7 @@ private:
 // async_sink class implementation
 ///////////////////////////////////////////////////////////////////////////////
 inline spdlog::details::async_log_helper::async_log_helper(formatter_ptr formatter, const std::vector<sink_ptr>& sinks, size_t queue_size):
-	_active(false),
+    _active(true),
     _formatter(formatter),
     _sinks(sinks),
     _q(queue_size),
@@ -172,97 +170,92 @@ inline spdlog::details::async_log_helper::~async_log_helper()
 inline void spdlog::details::async_log_helper::log(const details::log_msg& msg)
 {
     throw_if_bad_worker();
-
-    //Only if queue is full, enter wait loop
-    //if (!_q.push(std::unique_ptr < async_msg >(new async_msg(msg))))
-    //async_msg* as = new async_msg(msg);
-    //if (!_q.enqueue(std::unique_ptr<async_msg>(new async_msg(msg))))
-	if (!_q.enqueue(std::move(async_msg(msg))))
+    async_msg new_msg(msg);
+    if (!_q.enqueue(std::move(new_msg)))
     {
         auto last_op_time = clock::now();
         do
         {
             sleep_or_yield(last_op_time);
         }
-        while (!_q.enqueue(std::move(async_msg(msg))));
+        while (!_q.enqueue(std::move(new_msg)));
     }
 
 }
 
 inline void spdlog::details::async_log_helper::worker_loop()
 {
-	log_msg popped_log_msg;
     clock::time_point last_pop = clock::now();
-	_active = true;
     while (_active)
     {
-        q_type::item_type popped_msg;
+        //Dont die if there are still messages in the q to process
+        while(process_next_msg(last_pop));
+    }
+}
+
 
-        if (_q.dequeue(popped_msg))
+inline bool spdlog::details::async_log_helper::process_next_msg(clock::time_point& last_pop)
+{
+
+    async_msg incoming_async_msg;
+    log_msg incoming_log_msg;
+
+    if (_q.dequeue(incoming_async_msg))
     {
         last_pop = clock::now();
-
         try
         {
-                popped_msg.fill_log_msg(popped_log_msg);
-                _formatter->format(popped_log_msg);
+            incoming_async_msg.fill_log_msg(incoming_log_msg);
+            _formatter->format(incoming_log_msg);
             for (auto &s : _sinks)
-                    s->log(popped_log_msg);								
+                s->log(incoming_log_msg);
         }
         catch (const std::exception& ex)
         {
-                _last_workerthread_ex = std::make_shared<spdlog_ex>(ex.what());
+            _last_workerthread_ex = std::make_shared<spdlog_ex>(std::string("async_logger worker thread exception: ") + ex.what());
         }
         catch (...)
         {
-                _last_workerthread_ex = std::make_shared<spdlog_ex>("Unknown exception");
+            _last_workerthread_ex = std::make_shared<spdlog_ex>("async_logger worker thread exception");
         }
+        return true;
     }
     // sleep or yield if queue is empty.
     else
     {
         sleep_or_yield(last_pop);
-        }
+        return false;
     }
 }
 
-
 inline void spdlog::details::async_log_helper::set_formatter(formatter_ptr msg_formatter)
 {
     _formatter = msg_formatter;
 }
 
-inline void spdlog::details::async_log_helper::shutdown(const log_clock::duration& timeout)
-{
-    /*
-    if (timeout > std::chrono::milliseconds::zero())
-    {
-        auto until = log_clock::now() + timeout;
-        while (_q.approx_size() > 0 && log_clock::now() < until)
-        {
-            std::this_thread::sleep_for(std::chrono::milliseconds(5));
-        }
-    }
-    join_worker();
-     */
-}
-
 
-// Sleep or yield using the time passed since last message as a hint
+// Sleep,yield or return immediatly using the time passed since last message as a hint
 inline void spdlog::details::async_log_helper::sleep_or_yield(const clock::time_point& last_op_time)
 {
     using std::chrono::milliseconds;
-    using std::this_thread::sleep_for;
-    using std::this_thread::yield;
+    using namespace std::this_thread;
 
-    clock::duration sleep_duration;
     auto time_since_op = clock::now() - last_op_time;
-    if (time_since_op > milliseconds(1000))
-        sleep_for(milliseconds(500));
-    else if (time_since_op > milliseconds(1))
-        sleep_for(time_since_op / 2);
-    else
-        yield();
+
+    //spin upto 1 ms
+    if (time_since_op <= milliseconds(1))
+        return;
+
+    // yield upto 10ms
+    if (time_since_op <= milliseconds(10))
+        return yield();
+
+
+    // sleep for half of duration since last op
+    if (time_since_op <= milliseconds(100))
+        return sleep_for(time_since_op / 2);
+
+    return sleep_for(milliseconds(100));
 }
 
 //throw if the worker thread threw an exception or not active
@@ -282,17 +275,13 @@ inline void spdlog::details::async_log_helper::throw_if_bad_worker()
 inline void spdlog::details::async_log_helper::join_worker()
 {
     _active = false;
-    if (_worker_thread.joinable())
-    {
+
     try
     {
         _worker_thread.join();
     }
     catch (const std::system_error&) //Dont crash if thread not joinable
-        {
-        }
-    }
-
+    {}
 }
 
 

include/spdlog/details/async_logger_impl.h

@@ -34,18 +34,17 @@
 
 
 template<class It>
-inline spdlog::async_logger::async_logger(const std::string& logger_name, const It& begin, const It& end, size_t queue_size, const log_clock::duration& shutdown_duration) :
+inline spdlog::async_logger::async_logger(const std::string& logger_name, const It& begin, const It& end, size_t queue_size) :
     logger(logger_name, begin, end),
-    _shutdown_duration(shutdown_duration),
     _async_log_helper(new details::async_log_helper(_formatter, _sinks, queue_size))
 {
 }
 
-inline spdlog::async_logger::async_logger(const std::string& logger_name, sinks_init_list sinks, size_t queue_size, const log_clock::duration& shutdown_duration) :
-    async_logger(logger_name, sinks.begin(), sinks.end(), queue_size, shutdown_duration) {}
+inline spdlog::async_logger::async_logger(const std::string& logger_name, sinks_init_list sinks, size_t queue_size) :
+    async_logger(logger_name, sinks.begin(), sinks.end(), queue_size) {}
 
-inline spdlog::async_logger::async_logger(const std::string& logger_name, sink_ptr single_sink, size_t queue_size, const log_clock::duration& shutdown_duration) :
-    async_logger(logger_name, { single_sink }, queue_size, shutdown_duration) {}
+inline spdlog::async_logger::async_logger(const std::string& logger_name, sink_ptr single_sink, size_t queue_size) :
+    async_logger(logger_name, { single_sink }, queue_size) {}
 
 
 inline void spdlog::async_logger::_set_formatter(spdlog::formatter_ptr msg_formatter)
@@ -65,7 +64,6 @@ inline void spdlog::async_logger::_set_pattern(const std::string& pattern)
 inline void spdlog::async_logger::_stop()
 {
     set_level(level::OFF);
-    _async_log_helper->shutdown(_shutdown_duration);
 }
 
 inline void spdlog::async_logger::_log_msg(details::log_msg& msg)

include/spdlog/details/registry.h

@@ -61,7 +61,7 @@ public:
             return found->second;
         std::shared_ptr<logger> new_logger;
         if (_async_mode)
-            new_logger = std::make_shared<async_logger>(logger_name, sinks_begin, sinks_end, _async_q_size, _async_shutdown_duration);
+            new_logger = std::make_shared<async_logger>(logger_name, sinks_begin, sinks_end, _async_q_size);
         else
             new_logger = std::make_shared<logger>(logger_name, sinks_begin, sinks_end);
 
@@ -114,12 +114,11 @@ public:
             l.second->set_level(log_level);
     }
 
-    void set_async_mode(size_t q_size, const log_clock::duration& shutdown_duration)
+    void set_async_mode(size_t q_size)
     {
         std::lock_guard<std::mutex> lock(_mutex);
         _async_mode = true;
         _async_q_size = q_size;
-        _async_shutdown_duration = shutdown_duration;
     }
 
     void set_sync_mode()
@@ -153,7 +152,6 @@ private:
     level::level_enum _level = level::INFO;
     bool _async_mode = false;
     size_t _async_q_size = 0;
-    log_clock::duration _async_shutdown_duration;
 };
 }
 }

include/spdlog/details/spdlog_impl.h

@@ -133,9 +133,9 @@ inline void spdlog::set_level(level::level_enum log_level)
 }
 
 
-inline void spdlog::set_async_mode(size_t queue_size, const log_clock::duration& shutdown_duration)
+inline void spdlog::set_async_mode(size_t queue_size)
 {
-    details::registry::instance().set_async_mode(queue_size, shutdown_duration);
+    details::registry::instance().set_async_mode(queue_size);
 }
 
 inline void spdlog::set_sync_mode()

include/spdlog/spdlog.h

@@ -65,9 +65,8 @@ void set_level(level::level_enum log_level);
 //
 
 // Turn on async mode and set the queue size for each async_logger
-// shutdown_duration indicates max time to wait for the worker thread to log its messages before terminating.
 
-void set_async_mode(size_t queue_size, const log_clock::duration& shutdown_duration = std::chrono::seconds(5));
+void set_async_mode(size_t queue_size);
 // Turn off async mode
 void set_sync_mode();