private void setDonwloadSpeed(DownloadTask downloadTask) {
   long time = System.currentTimeMillis() - mStartDonwload;
   if (time > 0) {
     String speed = String.valueOf((downloadTask.getTotalSize() - mAlreadyDownloadSize) / time);
     if (DEBUG) {
       Log.d(TAG, "download apk speed : " + speed);
     }
     AppGameNetLogControll.getInstance().setDownloadSpeed(mChildThreadCode, speed);
   }
 }