CyclicBarrier
cycles around once all parties have called await and the barrier is opened. Hence the name.
So if you create it with 5 parties and there are 6 calls to await
the last one will trigger it to be waiting again for 4 more parties to join.
That's basically what happens here as you have the 1 extra await
call in your main. It is waiting for another runners-1 calls to happen.
The simple fix is to create the CyclicBarrier
with runners+1 parties.