He's not allocating through aux arrays, he's splitting the already allocated memory into log(n) layers. You can just track those aux arrays with math in the implementation.
It's probably not better than over-allocating except in memory constrained scenarios. But the overhead of funnel hashing is not high - it requires 0 extra memory
It's probably not better than over-allocating except in memory constrained scenarios. But the overhead of funnel hashing is not high - it requires 0 extra memory