ISSUE-2069: This kind of query could be stuck.
The sender failed to send the last packet to receiver.
Also, the failure does not be reportted to FE , so the query is not cancelled.
The error log sames as "body_size=xxxx from xxx:xxx is too large".
The reason of the socket is that the packet of the query is too big which is more then the max_body_size of brpc.
This commit add a config named brpc_max_body_size whcih is used to change the max_body_size of brpc.
Also, user can change the max_body_size directly on-the-fly by "http://host:brpc_port/flags".
ebdcfc21df