主从同步性能优化，主从同步性能测试。

kvs_rbtree_bin.c

@@ -469,7 +469,7 @@ static int kvs_rbtree_save_node(iouring_ctx_t *uring, int fd, off_t *current_off
     if (node == inst->nil) return 0;
 
     int rc = 0;
-
+	
     rc = kvs_rbtree_save_node(uring, fd, current_off, inst, node->left);
     if (rc < 0) return rc;
 
@@ -504,9 +504,12 @@ static int kvs_rbtree_save_node(iouring_ctx_t *uring, int fd, off_t *current_off
     for (int i = 0; i < count; i++) total += lens[i];
 
 	task_t *t = submit_write(uring, fd, bufs, lens, count, *current_off);
-
+	cleanup_finished_iouring_tasks();
 	
-	if (!t) { return -4; }
+	if(!t) {
+		perror("task init failed");
+		return -4;
+	}
 	
 	*current_off += (off_t) total;
 
@@ -527,7 +530,11 @@ int kvs_rbtree_save(iouring_ctx_t *uring, kvs_rbtree_t *inst, const char* filena
 
     int rc = kvs_rbtree_save_node(uring, fd, &current_off, inst, inst->root);
 
-    close(fd);
+	while (!uring_task_complete(uring)) {
+		usleep(1000);
+		cleanup_finished_iouring_tasks();
+	}
+	close(fd);
     return rc; 
 }