Before revision:  While a recently developed scheduling policy, called Delay Weighted Matching (DWM) , has been shown to be \log n) complexity hybrid scheduling policies are recently developed to guarantee } both rate-function delay-optimal (in the many-channel many-user asymptotic regime) and throughput-optimal (in general non-asymptotic setting), it has a high complexity O(n^5), which makes it impractical for modern OFDM systems .
After revision:  While a class of O(n^{2.5 \log n) complexity hybrid scheduling policies are recently developed to guarantee } both rate-function delay-optimal (in the many-channel many-user asymptotic regime) and throughput-optimal (in general non-asymptotic setting), it has a high complexity O(n^5), which makes it impractical for modern OFDM systems .