<div>Hi community, I am running a calculation on a system with 480 atoms in a unit cell of size approximately 37×37×37 Å. I used 128 CPUs with the wavelet Poisson solver, but encountered the following error: ******************************************************************************* * ___ * * / \ * * [ABORT] Index out of range in wavelet solver. Try decreasing the number of * * \___/ MPI processors, or adjust the PW_CUTOFF or cell size so that * * | 2*(number of RS grid points) matches the allowed FFT dimensions * * O/| (see ps_wavelet_fft3d.F) exactly. * * /| | * * / \ ps_wavelet_kernel.F:996 * ******************************************************************************* I tried reducing the number of CPUs to 48, and the calculation ran successfully. However, given the large system size, the calculation is very slow with fewer CPUs. My Questions: - Is there a way to use more CPUs with the Wavelet solver without encountering the FFT grid error? - Are there specific strategies (e.g., adjusting PW_CUTOFF, hybrid MPI+OpenMP) to ensure FFT grid compatibility while improving parallelization efficiency? Any suggestions would be greatly appreciated! Best regards, Xing </div> -- You received this message because you are subscribed to the Google Groups "cp2k" group. To unsubscribe from this group and stop receiving emails from it, send an email to <a href="mailto:cp2k+unsubscribe@googlegroups.com">cp2k+unsubscribe@googlegroups.com</a>. To view this discussion visit <a href="https://groups.google.com/d/msgid/cp2k/c4371bb7-5d8f-46e2-a3a4-98bd7f7c6705n%40googlegroups.com?utm_medium=email&utm_source=footer">https://groups.google.com/d/msgid/cp2k/c4371bb7-5d8f-46e2-a3a4-98bd7f7c6705n%40googlegroups.com</a>.