message: rsync optimized for speed
diff: @@ -686,24 +686,25 @@ void PikaServer::DBSyncSendFile(const std::string& ip, int port) {
  }
  // Get all files need to send
  std::vector<std::string> descendant;
  - if (!slash::GetDescendant(bg_path, descendant)) {
  - LOG(WARNING) << "Get Descendant when try to do db sync failed";
  + if (!slash::GetChildren(bg_path, descendant)) {
  + LOG(WARNING) << "Get child directory when try to do db sync failed";
  }
  // Iterate to send files
  int ret = 0;
  - std::string target_path;
  + std::string local_path, target_path;
  std::string module = kDBSyncModule + "_" + slash::IpPortString(host_, port_);
  std::vector<std::string>::iterator it = descendant.begin();
  slash::RsyncRemote remote(ip, port, module, g_pika_conf->db_sync_speed() * 1024);
  for (; it != descendant.end(); ++it) {
  - target_path = (*it).substr(bg_path.size() + 1);
  + local_path = bg_path + "/" + *it;
  + target_path = *it;
  +
  if (target_path == kBgsaveInfoFile) {
  continue;
  }
  // We need specify the speed limit for every single file
  - ret = slash::RsyncSendFile(*it, target_path, remote);
  -
  + ret = slash::RsyncSendFile(local_path, target_path, remote);
  if (0 != ret) {
  LOG(WARNING) << "rsync send file failed! From: " << *it
  