remove expire mechanism

from github#52

config.default.json.example

@@ -3,7 +3,6 @@
   "server_name" : "brubeck_debug",
   "dumpfile" : "./brubeck.dump",
   "capacity" : 15,
-  "expire" : 20,
   "http" : ":8080",
 
   "backends" : [

src/backend.c

@@ -30,7 +30,7 @@ static void *backend__thread(void *_ptr)
 			self->tick_time = now.tv_sec;
 
 			for (mt = self->queue; mt; mt = mt->next) {
-				if (mt->expire > BRUBECK_EXPIRE_DISABLED)
+				if (mt->state != BRUBECK_STATE_INACTIVE)
 					brubeck_metric_sample(mt, self->sample, self);
 			}
 

src/http.c

@@ -63,7 +63,7 @@ expire_metric(struct brubeck_server *server, const char *url)
 			server, url + strlen("/expire/"));
 
 	if (metric) {
-		metric->expire = BRUBECK_EXPIRE_DISABLED;
+		metric->state = BRUBECK_STATE_INACTIVE;
 		return MHD_create_response_from_data(
 				0, "", 0, 0);
 	}
@@ -76,8 +76,8 @@ send_metric(struct brubeck_server *server, const char *url)
 	static const char *metric_types[] = {
 		"gauge", "meter", "counter", "histogram", "timer", "internal"
 	};
-	static const char *expire_status[] = {
-		"disabled", "inactive", "active"
+	static const char *metric_status[] = {
+		"inactive", "active"
 	};
 
 	struct brubeck_metric *metric = safe_lookup_metric(
@@ -92,7 +92,7 @@ send_metric(struct brubeck_server *server, const char *url)
 #else
 			"shard", 0,
 #endif
-			"expire", expire_status[metric->expire]
+			"status", metric_status[metric->state]
 		);
 
 		char *jsonr = json_dumps(mj, JSON_INDENT(4) | JSON_PRESERVE_ORDER);

src/internal_sampler.c

@@ -58,7 +58,7 @@ brubeck_internal__sample(struct brubeck_metric *metric, brubeck_sample_cb sample
 	 * Mark the metric as active so it doesn't get disabled
 	 * by the inactive metrics pruner
 	 */
-	metric->expire = BRUBECK_EXPIRE_ACTIVE;
+	metric->state = BRUBECK_STATE_ACTIVE;
 }
 
 void brubeck_internal__init(struct brubeck_server *server)

src/metric.c

@@ -15,7 +15,7 @@ new_metric(struct brubeck_server *server, const char *key, size_t key_len, uint8
 	metric->key[key_len] = '\0';
 	metric->key_len = (uint16_t)key_len;
 
-	metric->expire = BRUBECK_EXPIRE_ACTIVE;
+	metric->state = BRUBECK_STATE_ACTIVE;
 	metric->type = type;
 	pthread_spin_init(&metric->lock, PTHREAD_PROCESS_PRIVATE);
 
@@ -49,6 +49,7 @@ gauge__record(struct brubeck_metric *metric, value_t value, value_t sample_freq,
 		} else {
 			metric->as.gauge.value = value;
 		}
+		metric->state= BRUBECK_STATE_ACTIVE;
 	}
 	pthread_spin_unlock(&metric->lock);
 }
@@ -61,6 +62,7 @@ gauge__sample(struct brubeck_metric *metric, brubeck_sample_cb sample, void *opa
 	pthread_spin_lock(&metric->lock);
 	{
 		value = metric->as.gauge.value;
+		metric->state = BRUBECK_STATE_INACTIVE;
 	}
 	pthread_spin_unlock(&metric->lock);
 
@@ -82,6 +84,7 @@ meter__record(struct brubeck_metric *metric, value_t value, value_t sample_freq,
 	pthread_spin_lock(&metric->lock);
 	{
 		metric->as.meter.value += value;
+		metric->state= BRUBECK_STATE_ACTIVE;
 	}
 	pthread_spin_unlock(&metric->lock);
 }
@@ -95,6 +98,7 @@ meter__sample(struct brubeck_metric *metric, brubeck_sample_cb sample, void *opa
 	{
 		value = metric->as.meter.value;
 		metric->as.meter.value = 0.0;
+		metric->state = BRUBECK_STATE_INACTIVE;
 	}
 	pthread_spin_unlock(&metric->lock);
 
@@ -124,6 +128,7 @@ counter__record(struct brubeck_metric *metric, value_t value, value_t sample_fre
 		}
 
 		metric->as.counter.previous = value;
+		metric->state= BRUBECK_STATE_ACTIVE;
 	}
 	pthread_spin_unlock(&metric->lock);
 }
@@ -137,6 +142,7 @@ counter__sample(struct brubeck_metric *metric, brubeck_sample_cb sample, void *o
 	{
 		value = metric->as.counter.value;
 		metric->as.counter.value = 0.0;
+		metric->state = BRUBECK_STATE_INACTIVE;
 	}
 	pthread_spin_unlock(&metric->lock);
 
@@ -155,6 +161,7 @@ histogram__record(struct brubeck_metric *metric, value_t value, value_t sample_f
 	pthread_spin_lock(&metric->lock);
 	{
 		brubeck_histo_push(&metric->as.histogram, value, sample_freq);
+		metric->state= BRUBECK_STATE_ACTIVE;
 	}
 	pthread_spin_unlock(&metric->lock);
 }
@@ -168,6 +175,7 @@ histogram__sample(struct brubeck_metric *metric, brubeck_sample_cb sample, void
 	pthread_spin_lock(&metric->lock);
 	{
 		brubeck_histo_sample(&hsample, &metric->as.histogram);
+		metric->state = BRUBECK_STATE_INACTIVE;
 	}
 	pthread_spin_unlock(&metric->lock);
 
@@ -187,11 +195,6 @@ histogram__sample(struct brubeck_metric *metric, brubeck_sample_cb sample, void
 		sample(metric->type, key, hsample.count / (double)backend->sample_freq, opaque);
 	}
 
-	/* if there have been no metrics during this sampling period,
-	 * we don't need to report any of the histogram samples */
-	if (hsample.count == 0.0)
-		return;
-
 	WITH_SUFFIX(".min") {
 		sample(metric->type, key, hsample.min, opaque);
 	}
@@ -333,6 +336,5 @@ brubeck_metric_find(struct brubeck_server *server, const char *key, size_t key_l
 	brubeck_atomic_inc(&metric->flow);
 #endif
 
-	metric->expire = BRUBECK_EXPIRE_ACTIVE;
 	return metric;
 }

src/metric.h

@@ -23,9 +23,8 @@ enum brubeck_aggregate_t {
 };
 
 enum {
-	BRUBECK_EXPIRE_DISABLED = 0,
-	BRUBECK_EXPIRE_INACTIVE = 1,
-	BRUBECK_EXPIRE_ACTIVE = 2
+	BRUBECK_STATE_INACTIVE = 0,
+	BRUBECK_STATE_ACTIVE = 1
 };
 
 struct brubeck_metric {
@@ -38,7 +37,7 @@ struct brubeck_metric {
 	pthread_spinlock_t lock;
 	uint16_t key_len;
 	uint8_t type;
-	uint8_t expire;
+	uint8_t state;
 
 	union {
 		struct {

src/server.c

@@ -63,16 +63,6 @@ update_proctitle(struct brubeck_server *server)
 	setproctitle("brubeck", buf);
 }
 
-static void
-expire_metric(struct brubeck_metric *mt, void *_)
-{
-	/* If this metric is not disabled, turn "inactive"
-	 * into "disabled" and "active" into "inactive"
-	 */
-	if (mt->expire > BRUBECK_EXPIRE_DISABLED)
-		mt->expire = mt->expire - 1;
-}
-
 static void
 dump_metric(struct brubeck_metric *mt, void *out_file)
 {
@@ -192,7 +182,6 @@ static void load_config(struct brubeck_server *server, const char *path)
 	json_t *backends, *samplers;
 
 	/* optional */
-	int expire = 0;
 	char *http = NULL;
 
 	server->name = "brubeck";
@@ -205,14 +194,13 @@ static void load_config(struct brubeck_server *server, const char *path)
 	}
 
 	json_unpack_or_die(server->config,
-		"{s?:s, s:s, s:i, s:o, s:o, s?:s, s?:i}",
+		"{s?:s, s:s, s:i, s:o, s:o, s?:s}",
 		"server_name", &server->name,
 		"dumpfile", &server->dump_path,
 		"capacity", &capacity,
 		"backends", &backends,
 		"samplers", &samplers,
-		"http", &http,
-		"expire", &expire);
+		"http", &http);
 
 	gh_log_set_instance(server->name);
 
@@ -224,7 +212,6 @@ static void load_config(struct brubeck_server *server, const char *path)
 	load_samplers(server, samplers);
 
 	if (http) brubeck_http_endpoint_init(server, http);
-	if (expire) server->fd_expire = load_timerfd(expire);
 }
 
 void brubeck_server_init(struct brubeck_server *server, const char *config)
@@ -237,7 +224,6 @@ void brubeck_server_init(struct brubeck_server *server, const char *config)
 
 	server->fd_signal = load_signalfd();
 	server->fd_update = load_timerfd(1);
-	server->fd_expire = -1;
 
 	/* init the memory allocator */
 	brubeck_slab_init(&server->slab);
@@ -272,7 +258,7 @@ static int signal_triggered(struct pollfd *fd)
 
 int brubeck_server_run(struct brubeck_server *server)
 {
-	struct pollfd fds[3];
+	struct pollfd fds[2];
 	int nfd = 2;
 	size_t i;
 
@@ -284,11 +270,6 @@ int brubeck_server_run(struct brubeck_server *server)
 	fds[1].fd = server->fd_update;
 	fds[1].events = POLLIN;
 
-	if (server->fd_expire >= 0) {
-		fds[2].fd = server->fd_expire;
-		fds[2].events = POLLIN;
-		nfd++;
-	}
 
 	server->running = 1;
 	log_splunk("event=listening");
@@ -315,11 +296,6 @@ int brubeck_server_run(struct brubeck_server *server)
 			update_flows(server);
 			update_proctitle(server);
 		}
-
-		if (timer_elapsed(&fds[2])) {
-			log_splunk("event=expire_metrics");
-			brubeck_hashtable_foreach(server->metrics, &expire_metric, NULL);
-		}
 	}
 
 	for (i = 0; i < server->active_backends; ++i)

src/server.h

@@ -27,7 +27,6 @@ struct brubeck_server {
 	int active_samplers;
 
 	int fd_signal;
-	int fd_expire;
 	int fd_update;
 
 	struct brubeck_slab slab;