The paper presents a novel approach to increase the performance and/or throughput of iterative belief propagation (BP) decoding of low density parity check (LDPC) codes. The proposed approach is based on utilizing the decoder idle time by introducing two queue s: one at the decoder input and the other at the decoder output. At the presence of an input queue, the decoder runs extra iterations beyond the maximum allowable iterations as long as the input queue is not full. The function of the output queue is to preserve decoder timing, guaranteeing frames to be decoded within a fixed time similar to a conventional LDPC decoder, making it practical for real time applications. Simulation results for a rate ½ (1024,512) progressive edge-growth (PEG) LDPC code show that the proposed approach can increase the decoder performance up to 69% keeping the same throughput, or doubling the throughput while keeping performance almost the same.