REMOVE STAT OBSERVERS

nano/lib/stats.cpp

@@ -432,7 +432,7 @@ void nano::stats::update (key key_a, uint64_t value)
 		// Counters
 		auto old (entry->counter.get_value ());
 		entry->counter.add (value, has_sampling ()); // Only update timestamp when sampling is enabled as this has a performance impact
-		entry->count_observers.notify (old, entry->counter.get_value ());
+
 		if (has_interval_counter () || has_sampling ())
 		{
 			auto now = std::chrono::steady_clock::now (); // Only sample clock if necessary as this impacts node performance due to frequent usage
@@ -461,12 +461,6 @@ void nano::stats::update (key key_a, uint64_t value)
 					entry->samples.push_back (entry->sample_current);
 					entry->sample_current.set_value (0);
 
-					if (!entry->sample_observers.empty ())
-					{
-						auto snapshot (entry->samples);
-						entry->sample_observers.notify (snapshot);
-					}
-
 					// Log sink
 					duration = now - log_last_sample_writeout;
 					if (config.log_interval_samples > 0 && duration.count () > config.log_interval_samples)

nano/lib/stats.hpp

@@ -143,12 +143,6 @@ class stat_entry final
 
 	/** Optional histogram for this entry */
 	std::unique_ptr<stat_histogram> histogram;
-
-	/** Zero or more observers for samples. Called at the end of the sample interval. */
-	nano::observer_set<boost::circular_buffer<stat_datapoint> &> sample_observers;
-
-	/** Observers for count. Called on each update. */
-	nano::observer_set<uint64_t, uint64_t> count_observers;
 };
 
 /** Log sink interface */
@@ -316,32 +310,6 @@ class stats final
 	 */
 	void add (stat::type type, stat::detail detail, stat::dir dir, uint64_t value);
 
-	/**
-	 * Add a sampling observer for a given counter.
-	 * The observer receives a snapshot of the current sampling. Accessing the sample buffer is thus thread safe.
-	 * To avoid recursion, the observer callback must only use the received data point snapshop, not query the stat object.
-	 * @param observer The observer receives a snapshot of the current samples.
-	 */
-	void observe_sample (stat::type type, stat::detail detail, stat::dir dir, std::function<void (boost::circular_buffer<stat_datapoint> &)> observer)
-	{
-		get_entry (key{ type, detail, dir })->sample_observers.add (observer);
-	}
-
-	void observe_sample (stat::type type, stat::dir dir, std::function<void (boost::circular_buffer<stat_datapoint> &)> observer)
-	{
-		observe_sample (type, stat::detail::all, dir, observer);
-	}
-
-	/**
-	 * Add count observer for a given type, detail and direction combination. The observer receives old and new value.
-	 * To avoid recursion, the observer callback must only use the received counts, not query the stat object.
-	 * @param observer The observer receives the old and the new count.
-	 */
-	void observe_count (stat::type type, stat::detail detail, stat::dir dir, std::function<void (uint64_t, uint64_t)> observer)
-	{
-		get_entry (key{ type, detail, dir })->count_observers.add (observer);
-	}
-
 	/** Returns a potentially empty list of the last N samples, where N is determined by the 'capacity' configuration */
 	boost::circular_buffer<stat_datapoint> * samples (stat::type type, stat::detail detail, stat::dir dir)
 	{