Time required to enter the packet in specific queue :
Time complexity is O(logn) as we have queues in sorted order.so insertion of a packet in a queue will take very little time.
Howevere that is not in many cases because this scheme is based on the fact that at any particular time number of active flows are ver less than total number of flows present in a particular line.So even if we keep number of queues less than total number of flows than it is possible in many cases that number of queues will be more than total number of active flows.