diff --git a/core/audio.c b/core/audio.c
index ad362657..10ed311b 100644
--- a/core/audio.c
+++ b/core/audio.c
@@ -93,7 +93,7 @@ static gboolean __audio_message(GstBus *bus, GstMessage *message, gpointer data)
 	return true;
 }
 
-static void __audio_init_idle(void *data)
+static bool __audio_init_idle(void *data)
 {
 	unsigned int track;
 
@@ -102,6 +102,7 @@ static void __audio_init_idle(void *data)
 		file_close(&audio_file);
 		__audio_load(track_get(track), GST_STATE_PAUSED);
 	}
+	return true;
 }
 
 
diff --git a/core/collection.c b/core/collection.c
index 13a69c65..89578fe8 100644
--- a/core/collection.c
+++ b/core/collection.c
@@ -18,7 +18,7 @@ struct scan_data {
 	gchar *sd_path;
 };
 
-static void __scan_dir(void *);
+static bool __scan_dir(void *);
 
 
 #ifdef CONFIG_TESTING
@@ -61,7 +61,7 @@ static void __scan_path(struct scan_data *scan, const gchar *name)
 	g_free(path);
 }
 
-static void __scan_dir(void *data)
+static bool __scan_dir(void *data)
 {
 	struct scan_data *scan = data;
 	const char *name;
@@ -84,9 +84,10 @@ out:
 	/* Allocated by __scan_dir_later() */
 	g_free(scan->sd_path);
 	g_free(scan);
+	return true;
 }
 
-static void __validate_library(void *data)
+static bool __validate_library(void *data)
 {
 	struct library *library = data;
 	struct db_entry *dbe, *next;
@@ -105,14 +106,16 @@ static void __validate_library(void *data)
 
 		if (access < 0) {
 			if (collection_check_library(library) < 0)
-				return;
+				return true;
 			queue_remove_all(&c_queue, track);
 			track_remove(track);
 		}
 	}
+
+	return true;
 }
 
-void __collection_init_idle(void *data)
+bool __collection_init_idle(void *data)
 {
 	struct db_entry *track, *next;
 	unsigned int i, n = 0;
@@ -146,6 +149,7 @@ void __collection_init_idle(void *data)
 	queue_set_flag(&c_queue, Q_SAVE_FLAGS);
 
 	collection_update_all();
+	return true;
 }
 
 
diff --git a/core/containers/database.c b/core/containers/database.c
index 86a4f426..96f74e65 100644
--- a/core/containers/database.c
+++ b/core/containers/database.c
@@ -129,9 +129,15 @@ void db_load(struct database *db)
 	file_close(&db->db_file);
 }
 
+static bool __db_load_idle(struct database *db)
+{
+	db_load(db);
+	return true;
+}
+
 void db_load_idle(struct database *db)
 {
-	idle_schedule(IDLE_SYNC, IDLE_FUNC(db_load), db);
+	idle_schedule(IDLE_SYNC, IDLE_FUNC(__db_load_idle), db);
 }
 
 struct db_entry *db_insert(struct database *db, const gchar *key)
diff --git a/core/idle.c b/core/idle.c
index 3d1d9712..ef673263 100644
--- a/core/idle.c
+++ b/core/idle.c
@@ -6,7 +6,7 @@
 
 
 struct idle_task {
-	void (*idle_func)(void *);
+	bool (*idle_func)(void *);
 	void  *idle_data;
 	enum   idle_sync_t idle_sync;
 };
@@ -17,16 +17,20 @@ static unsigned int queued   = 0;
 static unsigned int serviced = 0;
 
 
-void __idle_run_task(struct idle_task *task)
+bool __idle_run_task(struct idle_task *task)
 {
-	task->idle_func(task->idle_data);
-	g_free(task);
-	g_atomic_int_inc(&serviced);
+	bool finished = task->idle_func(task->idle_data);
+	if (finished) {
+		g_free(task);
+		g_atomic_int_inc(&serviced);
+	}
+	return finished;
 }
 
 void __idle_thread(gpointer task, gpointer data)
 {
-	__idle_run_task(task);
+	if (!__idle_run_task(task))
+		g_thread_pool_push(idle_pool, task, NULL);
 }
 
 
@@ -51,7 +55,7 @@ void idle_deinit()
 	serviced = 0;
 }
 
-void idle_schedule(enum idle_sync_t sync, void (*func)(void *), void *data)
+void idle_schedule(enum idle_sync_t sync, bool (*func)(void *), void *data)
 {
 	struct idle_task *task = g_malloc(sizeof(struct idle_task));
 	task->idle_func = func;
@@ -70,8 +74,8 @@ bool idle_run_task()
 		task = g_queue_pop_head(&idle_queue);
 		if (task->idle_sync == IDLE_ASYNC)
 			g_thread_pool_push(idle_pool, task, NULL);
-		else
-			__idle_run_task(task);
+		else if (!__idle_run_task(task))
+			g_queue_push_tail(&idle_queue, task);
 	}
 
 	if (g_atomic_int_get(&queued) != g_atomic_int_get(&serviced))
diff --git a/core/tempq.c b/core/tempq.c
index 5ecd3413..09941d23 100644
--- a/core/tempq.c
+++ b/core/tempq.c
@@ -57,17 +57,18 @@ static void __tempq_write_queue(struct queue *queue)
 	file_writef(&tempq_file, "\n");
 }
 
-static void __tempq_init_idle(void *data)
+static bool __tempq_init_idle(void *data)
 {
 	unsigned int num, i;
 
 	if (!file_open(&tempq_file, OPEN_READ))
-		return;
+		return true;
 
 	file_readf(&tempq_file, "%u", &num);
 	for (i = 0; i < num; i++)
 		__tempq_read_queue();
 	file_close(&tempq_file);
+	return true;
 }
 
 
diff --git a/gui/collection.c b/gui/collection.c
index 31dd97a9..1a7c6282 100644
--- a/gui/collection.c
+++ b/gui/collection.c
@@ -191,7 +191,7 @@ static void __collection_removed(struct queue *queue, unsigned int pos)
 	gui_sidebar_set_size(gui_queue(queue));
 }
 
-void __gui_collection_init_idle()
+bool __gui_collection_init_idle()
 {
 	struct db_entry *library, *next;
 	GtkTreeIter parent, iter, last;
@@ -206,6 +206,7 @@ void __gui_collection_init_idle()
 		gtk_tree_store_insert_before(GTK_TREE_STORE(c_model), &iter, &parent, &last);
 		__collection_set_library(&iter, LIBRARY(library));
 	}
+	return true;
 }
 
 
diff --git a/include/core/idle.h b/include/core/idle.h
index 071231c5..0b3c12e5 100644
--- a/include/core/idle.h
+++ b/include/core/idle.h
@@ -20,7 +20,7 @@ enum idle_sync_t {
 	IDLE_ASYNC, /* Run task in a separate thread. */
 };
 
-#define IDLE_FUNC(x) ((void (*)(void *))x)
+#define IDLE_FUNC(x) ((bool (*)(void *))x)
 
 
 /* Called to initialize the idle queue. */
@@ -30,7 +30,7 @@ void idle_init();
 void idle_deinit();
 
 /* Called to schedule a function to run later. */
-void idle_schedule(enum idle_sync_t, void (*)(void *), void *);
+void idle_schedule(enum idle_sync_t, bool (*)(void *), void *);
 
 /*
  * Called to run the next task on the idle queue.
diff --git a/tests/core/idle.c b/tests/core/idle.c
index 0f025992..fe77156e 100644
--- a/tests/core/idle.c
+++ b/tests/core/idle.c
@@ -9,11 +9,12 @@
 static unsigned int cur = -1;
 static bool func_passed = false;
 
-static void inc_cur(void *data)
+static bool inc_cur(void *data)
 {
 	unsigned int expected = GPOINTER_TO_INT(data);
 	cur++;
 	func_passed = (cur == expected);
+	return true;
 }
 
 
diff --git a/tests/gui/idle.c b/tests/gui/idle.c
index c2cd1495..370640b2 100644
--- a/tests/gui/idle.c
+++ b/tests/gui/idle.c
@@ -18,11 +18,12 @@ static bool func_passed = false;
 struct core_init_data init_data;
 static GMainLoop *main_loop;
 
-static void inc_cur(void *data)
+static bool inc_cur(void *data)
 {
 	unsigned int expected = GPOINTER_TO_INT(data);
 	cur++;
 	func_passed = (cur == expected);
+	return true;
 }
 
 static int test_on_idle()