There's nothing requiring that an unrolled linked list has a fixed number of elements per node. It's just easier to reason about the performance results by fixi

There's nothing requiring that an unrolled linked list has a fixed number of elements per node. It's just easier to reason about the performance results by fixing the number. This looks like an unrolled linked list with variable elements per node, which allows it to do things like allocate a single node for an entire bulk add operation.