fix dbdump so that it doesn't crash lsd when dumping a database while lsd is running
fix dbdump so that it doesn't crash lsd when dumping a database while lsd is running

weidezhang/dht,sit/dht,sit/dht,weidezhang/dht,weidezhang/dht,weidezhang/dht,sit/dht,weidezhang/dht,sit/dht,sit/dht