An asynchronous GVT computing algorithm in neuron time warp-multi thread

Multi-threaded Parallel Discrete Event Simulation (PDES) is promising to achieve high performance. Generally employing a collection of multi-core nodes is necessary to accomplish large scale PDES, which makes it running in a hybrid of distributed and shared memory platform. Present Global Virtual Time (GVT) computing algorithms are suitable for pure distributed or shared memory platform. In this paper we present an asynchronous GVT computing algorithm in Neuron Time Warp-Multi Thread (NTW-MT) simulator for stochastic simulation in NEURON project. GVT is computed asynchronously both within and among processes, which is the first try in multi-threaded PDES as far as we know. Then we prove this algorithm can compute a valid GVT at any wall clock time, and conclude it has less computational cost through analysing the cost and delay. Finally we show results of simulating a calcium wave model in an unbranched apical dendrite of a hippocampal pyramidal neuron.