[PATCH -nvmeof] selftest: Add test for keep-alive expired with live io

[Sagi Grimberg]

> +echo "Running ifconfig $HOST_NIC up/down for $NUM_TEST times"
> +for i in `seq $NUM_TEST` ; do
> +	ifconfig $HOST_NIC down
> +	sleep $(( 10 + ($RANDOM & 0x7) ))
> +	ifconfig $HOST_NIC up
> +	sleep $(( 10 + ($RANDOM & 0x7) ))
> +done
> +
> +sleep 5
> +killall -9 fio

Why SIGKILL? why so harsh?