• V. O. Bohaienko V. M. Glushkov Institute of Cybernetics of NAS of Ukraine, Kyiv, Ukraine
  • A. V. Gladky V. M. Glushkov Institute of Cybernetics of NAS of Ukraine, Kyiv, Ukraine
Keywords: moisture transport, fractional derivatives, multithreading, irrigation


The paper studies the performance of multithreaded parallel implementation of a finite-difference solver for a two-dimensional space-fractional generalization of Richards equation. For numerical solution we used implicit Crank-Nicholson scheme with L1-approximation of Caputo fractional derivative and TFQMR linear systems’ solver. OpenMP implementation was tested on three CPUs — server Intel Xeon Bronze 3104 and AMD EPYC 7542 along with laptop AMD Ryzen 3 5300U. Testing results show that the proposed implementation can give close-to-linear acceleration when executing on up to 8 cores. On high-performance AMD EPYC maximal acceleration was achieved when 32-64 cores were used showing limited scalability of the algorithms on such a CPU.


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