[0.99.41] delayed_usecs statistics

git-svn-id: svn+ssh://jackaudio.org/trunk/jack@856 0c269be4-1314-0410-8aa9-9f06e86f4224

jack/internal.h

@@ -139,6 +139,7 @@ typedef struct {
     int32_t		  has_capabilities;
     float                 cpu_load;
     float		  xrun_delayed_usecs;
+    float		  max_delayed_usecs;
     uint32_t		  port_max;
     int32_t		  engine_ok;
     jack_port_type_id_t	  n_port_types;

jack/jack.h

@@ -755,6 +755,21 @@ jack_nframes_t jack_last_frame_time (const jack_client_t *client);
  */
 float jack_cpu_load (jack_client_t *client);
 
+/**
+ * @return the maximum delay reported by the backend since
+ * startup or reset.  When compared to the period size in usecs, this
+ * can be used to estimate the ideal period size for a given setup.
+ */
+float jack_get_max_delayed_usecs (jack_client_t *client);
+
+/**
+ * Reset the maximum delay counter.  This would be useful
+ * to estimate the effect that a change to the configuration of a running
+ * system (e.g. toggling kernel preemption) has on the delay
+ * experienced by JACK, without having to restart the JACK engine.
+ */
+void jack_reset_max_delayed_usecs (jack_client_t *client);
+	
 /**
  * @return the pthread ID of the thread running the JACK client side
  * code.

jackd/engine.c

@@ -1685,6 +1685,7 @@ jack_engine_new (int realtime, int rtpriority, int do_mlock, int do_unlock,
 	engine->control->do_munlock = do_unlock;
 	engine->control->cpu_load = 0;
 	engine->control->xrun_delayed_usecs = 0;
+	engine->control->max_delayed_usecs = 0;
 
 	engine->control->frame_timer.frames = 0;
 	engine->control->frame_timer.reset_pending = 0;
@@ -1772,6 +1773,9 @@ jack_engine_delay (jack_engine_t *engine, float delayed_usecs)
 
 	engine->control->xrun_delayed_usecs = delayed_usecs;
 
+	if (delayed_usecs > engine->control->max_delayed_usecs)
+		engine->control->max_delayed_usecs = delayed_usecs;
+
 	event.type = XRun;
 
 	jack_lock_graph (engine);
@@ -2004,6 +2008,8 @@ jack_run_one_cycle (jack_engine_t *engine, jack_nframes_t nframes,
 	}
 
 	jack_engine_post_process (engine);
+	if (delayed_usecs > engine->control->max_delayed_usecs)
+		engine->control->max_delayed_usecs = delayed_usecs;
 	ret = 0;
 
   unlock:
@@ -2150,6 +2156,8 @@ jack_engine_delete (jack_engine_t *engine)
 
 	VERBOSE (engine, "last xrun delay: %.3f usecs\n",
 		engine->control->xrun_delayed_usecs);
+	VERBOSE (engine, "max delay reported by backend: %.3f usecs\n",
+		engine->control->max_delayed_usecs);
 
 	/* free engine control shm segment */
 	engine->control = NULL;

libjack/ChangeLog

@@ -1,3 +1,10 @@
+2004-12-27  Jack O'Quin  <joq@io.com>
+
+	* new API functions jack_get_max_delayed_usecs() and
+	jack_reset_max_delayed_usecs()
+
+	* add US-X2Y USB device support to ALSA backend
+
 2004-11-28  Jack O'Quin  <joq@io.com>
 
 	* removed deprecated function jack_set_server_dir().

libjack/client.c

@@ -1994,6 +1994,18 @@ jack_get_xrun_delayed_usecs (jack_client_t *client)
 	return client->engine->xrun_delayed_usecs;
 }
 
+float
+jack_get_max_delayed_usecs (jack_client_t *client)
+{
+	return client->engine->max_delayed_usecs;
+}
+
+void
+jack_reset_max_delayed_usecs (jack_client_t *client)
+{
+	client->engine->max_delayed_usecs =  0.0f;
+}
+
 pthread_t
 jack_client_thread_id (jack_client_t *client)
 {