Memory error while running production MD after NVT and NPT equilibriation phases

GROMACS version:2021.4
GROMACS modification:No
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Hi everyone, when I tried to run production MD, after running the NVT and NPT equilibriation phases, I got a memory error as follows :

GROMACS: gmx mdrun, version 2021.4-Ubuntu-2021.4-2
Executable: /usr/bin/gmx
Data prefix: /usr
Working dir: /mnt/d/pc_in_dmso/pc3
Command line:
gmx mdrun -deffnm md_0_1

Reading file md_0_1.tpr, VERSION 2021.4-Ubuntu-2021.4-2 (single precision)
Changing nstlist from 10 to 100, rlist from 1 to 1

Using 1 MPI thread
Using 2 OpenMP threads

Program: gmx mdrun, version 2021.4-Ubuntu-2021.4-2
Source file: src/gromacs/utility/smalloc.cpp (line 227)

Fatal error:
Not enough memory. Failed to allocate 18446744072720827419 aligned elements of
size 4 for grid->grid
(called from file ./src/gromacs/ewald/pme_grid.cpp, line 572)

The dimension of my cubic box is 5.548 nm and it is filled with 71 residues of solute molecules (923 atoms), in 1000 residues of solvent dimethyl sulfoxide-d6. Previously I had minimised the energy of the box with integrator=steep and equilibriated the system with NVT/NPT 100 ps.

It may happen when NPT-equilibration is conducted using Parrinello-Rahman barostat which expands the simulation box dramatically. Replacing
pcoupl = Parrinello-Rahman
in the npt.mdp file with
pcoupl = C-rescale
resolves the problem.