The Waveform IQMR Accelerated Technique for Parallel Transient Simulation of Semiconductor Devices

In this paper, we mainly study the parallelization aspects of the accelerated waveform relaxation algorithms for the transient simulation of semiconductor devices on parallel distributed memory computers since these method are competitive with standard pointwise methods on serial machines, but are significantly faster on parallel computers. Here we propose an improved version of the quasi-minimal residual (IQMR) method by using the Lanczos process as a major component combining elements of numerical stability and parallel algorithm design, for solving the resulting sequence of time-varying sparse linear differential-algebraic initial-value problems (IVP) arising at each linearization step with waveform Newton. For Lanczos process, stability is obtained by a coupled two-term procedure that generates Lanczos vectors scaled to unit length. The algorithm is derived such that all inner products and matrix-vector multiplications of a single iteration step are independent and communication ti..

An Efficient Accelerated Waveform Method for Parallel Transient Simulation of Semiconductor Devices

In this paper, we mainly study the parallelization aspects of the accelerated waveform relaxation algorithms for the transient simulation of semiconductor devices on parallel distributed memory computers since these methods are competitive with standard pointwise methods on serial machines, but are significantly faster on parallel computers. Here we propose an improved version of the quasi-minimal residual (IQMR) method by using the Lanczos process as a major component combining elements of numerical stability and parallel algorithm design, for solving the resulting sequence of time-varying sparse linear differential-algebraic initial-value problems (IVP) arising at each linearization step with waveform Newton. Additionally an efficient preconditioning technique IMGS preconditioner, where the global communication is reduced by either identify operations that may be executed while communication takes place, or to combine the messages for several global communications, to improve the eff..