Failed cpimport, due to a Connection Timed Out, leads to one having to restartSystem

A failed cpimort left the system in a state where a full restart is needed:

/usr/local/mariadb/columnstore/bin/cpimport db table /path/to/file.tab -s '\t' -m 1
RESPONSE:
Could not connect to pm3_WriteEngineServer: InetStreamSocket::connect: connection timed out
2018-10-23 11:18:50 (28405) ERR : Problem in connecting to PM
2018-10-23 11:18:50 (28405) ERR : Error in connection setup.

This failed cpimport (which is apparently due to some timeout between UM and PM3) left some table locks that could not be removed, and the entire system needed restarted.

So this is a request to see if we can code something to help recover from that.