Export 9389279 block takes less than 1 hour.
I used command:
docker run -d --rm -v $PWD/full-ethereum-node:/root/.ethereum ethereum/client-go export /root/.ethereum/geth/chaindata/9389270.backup 0 9389270
But import whole 9389270.backup file is so slow, that it is equal to sync node from genesis block with the network.
The testing environment was: Intel ...