Today I read a paper titled “Parallelization of a Dynamic Monte Carlo Algorithm: a Partially Rejection-Free Conservative Approach”
The abstract is:
We experiment with a massively parallel implementation of an algorithm for simulating the dynamics of metastable decay in kinetic Ising models.
The parallel scheme is directly applicable to a wide range of stochastic cellular automata where the discrete events (updates) are Poisson arrivals.
For high performance, we utilize a continuous-time, asynchronous parallel version of the n-fold way rejection-free algorithm.
Each processing element carries an lxl block of spins, and we employ the fast SHMEM-library routines on the Cray T3E distributed-memory parallel architecture.
Different processing elements have different local simulated times.
To ensure causality, the algorithm handles the asynchrony in a conservative fashion.
Despite relatively low utilization and an intricate relationship between the average time increment and the size of the spin blocks, we find that for sufficiently large l the algorithm outperforms its corresponding parallel Metropolis (non-rejection-free) counterpart.
As an example application, we present results for metastable decay in a model ferromagnetic or ferroelectric film, observed with a probe of area smaller than the total system.