diff --git a/sfile.c b/sfile.c
index 20a410f9..f8c41cb5 100644
--- a/sfile.c
+++ b/sfile.c
@@ -1053,13 +1053,8 @@ sfile_add_value (SFileOutput *file,
     TransitionType type;
     
     file->state = state_transition_begin (file->state, name, &tmp_type, NULL);
-    g_return_if_fail (file->state && tmp_type == begin);
-
     file->state = state_transition_text (file->state, &type, NULL);
-    g_return_if_fail (file->state && type == value);
-    
     file->state = state_transition_end (file->state, name, &tmp_type, NULL);
-    g_return_if_fail (file->state && tmp_type == end);
 
     return type;
 }
diff --git a/sysprof-module.c b/sysprof-module.c
index 05a1cfa5..6d516a08 100644
--- a/sysprof-module.c
+++ b/sysprof-module.c
@@ -263,38 +263,68 @@ generate_stack_trace(struct task_struct *task,
 struct work_struct work;
 static int in_queue;
 
+static task_t *trace_tasks[256];
+
 static void
 do_generate (void *data)
 {
-	struct task_struct *task = data;
 	struct task_struct *p;
+	int i, target;
 
-	in_queue = 0;
-
-	/* Make sure the task still exists */
+	/* Mark all trace tasks that still exists */
 	for_each_process (p) {
-		if (p == task) {
-			generate_stack_trace(task, head);
+		for (i = 0; i < 256; ++i) {
+			if (!trace_tasks[i])
+				goto next_process;
+		
+			if (trace_tasks[i] == p) {
+				trace_tasks[i] = (task_t *)((long)trace_tasks[i] | 0x01);
+			}
+		}
+	next_process:
+		;
+	}
 
-			if (head++ == &stack_traces[N_TRACES - 1])
-				head = &stack_traces[0];
-			
-			wake_up (&wait_for_trace);
-			
-			return;
+	target = 0;
+	for (i = 0; i < 256; ++i) {
+		if (trace_tasks[i] == NULL) {
+			break;
+		}
+		else if ((int)(trace_tasks[i]) & 0x01) {
+			trace_tasks[target++] = (task_t *)((int)trace_tasks[i] & ~0x01);
+		}
+		else {
+			trace_tasks[i] = NULL;
 		}
 	}
+
+	/* Generate the stack traces */
+	for (i = 0; i < 256; ++i) {
+		if (!trace_tasks[i])
+			break;
+		
+		generate_stack_trace(trace_tasks[i], head);
+		
+		if (head++ == &stack_traces[N_TRACES - 1])
+			head = &stack_traces[0];
+		
+		wake_up (&wait_for_trace);
+		
+		trace_tasks[i] = NULL;
+	}
+	
+	in_queue = 0;
 }
 
 static void
-queue_generate_stack_trace (struct task_struct *cur)
+queue_generate_stack_trace (void)
 {
 	if (in_queue)
 		return;
 
 	in_queue = 1;
 	
-	INIT_WORK (&work, do_generate, cur);
+	INIT_WORK (&work, do_generate, NULL);
 
 	schedule_work (&work);
 }
@@ -303,14 +333,19 @@ static void
 on_timer(unsigned long dong)
 {
 	struct task_struct *p;
+	int i;
 
-	static const int cpu_profiler = 0; /* set to 0 to profile disk */
-	
+	static const int cpu_profiler = 1; /* set to 0 to profile disk */
+
+	i = 0;
 	for_each_process (p) {
 		if (p->state == (cpu_profiler? TASK_RUNNING : TASK_UNINTERRUPTIBLE)) {
-			queue_generate_stack_trace (p);
+			trace_tasks[i++] = p;
 		}
 	}
+
+	if (i)
+		queue_generate_stack_trace ();
 	
 	add_timeout (INTERVAL, on_timer);
 }
@@ -333,6 +368,7 @@ procfile_read(char *buffer,
 }
 
 struct proc_dir_entry *trace_proc_file;
+
 static unsigned int
 procfile_poll(struct file *filp, poll_table *poll_table)
 {