Matrix-free vs. matrix-based real-time reconstruction on CPU and GPU
In this talk, we focus on the Finite Element Wavelet Hybrid Algorithm (FEWHA), which is a real-time reconstruction algorithm that can be formulated either in a matrix-free and iterative way or as a matrix-vector-multiplication (MVM). The iterative approach has advantages such as no precomputation of the inverse and on the fly parameter updates, but does not support pipelining. We study the performance of the matrix-based vs. the matrix-free FEWHA in simulations for a MORFEO like test setting. MORFEO is an Adaptive Optics system of the ELT and fulfilling its real-time requirements is a challenging task. We will study whether the iterative approach affects the reconstruction quality in comparison to a direct solver. Moreover, we look in detail at the computational performance of the matrix-free FEWHA on a CPU vs. the matrix-based version on a GPU.
Bernadett Stadler, RICAM