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Error ocurring in ALDA convergence with FxcGRLc and NGsBlkXd for CH4.

Posted: Mon Aug 17, 2026 5:12 am
by Kartik.Varshney
Dear Yambo developers,

I am trying to calculate the TDDFT optical response of a CH4 molecule using Yambo 5.3.0. The calculation stops during the setup of observables and procedures with the following error:

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[ERROR] STOP signal received while in[04.01] Setup: observables and procedures
[ERROR] Impossible to define an appropriate parallel structure
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The same error is reported by the MPI processes. For example:
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P1-n70: [ERROR] STOP signal received while in[04.01] Setup: observables and procedures
P1-n70: [ERROR] Impossible to define an appropriate parallel structure

P10-n70: [ERROR] STOP signal received while in[04.01] Setup: observables and procedures
P10-n70: [ERROR] Impossible to define an appropriate parallel structure
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I am running the calculation on an HPC cluster using SLURM with 4 nodes and 28 MPI tasks per node, i.e. 112 MPI processes.
My Yambo input is:
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optics
chi
tddft

NLogCPUs=0
PAR_def_mode= "memory"

X_CPU= "1.1.1.14.8"
X_ROLEs= "g.q.k.c.v"
X_nCPU_LinAlg_INV=1
X_Threads=0

Chimod= "ALDA"
FxcGRLc= 200 eV
NGsBlkXd= 100 eV

% QpntsRXd
1 | 1 |
%

% BndsRnXd
1 | 11 |
%

% EnRngeXd
0.00000 | 20.00000 | eV
%

% DmRngeXd
0.100000 | 0.100000 | eV
%

ETStpsXd= 151

% LongDrXd
1.000000 | 0.000000 | 0.000000 |
%
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The SLURM job script is:
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#!/bin/bash
#SBATCH --job-name=yambo
#SBATCH --partition=test2
#SBATCH --nodes=4
#SBATCH --ntasks-per-node=28
#SBATCH --output=out_yambo.out
#SBATCH --error=err_yambo.err

module purge
module load compilers/intel/intel-OneAPI-2021.1

export PATH=$HOME/yambo-5.3.0/bin:$PATH

cd $SLURM_SUBMIT_DIR

mpirun -np $SLURM_NTASKS yambo
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The Yambo executable reports:
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Version 5.3.0 Revision 23959
MPI+OpenMP+SLK+HDF5_MPI_IO Build
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I would like to understand why Yambo cannot construct an appropriate parallel structure for this calculation. And how does that other error that says stop signal received while in[04.01] will be resolved?
In particular, I would appreciate advice on whether my `X_CPU`/`X_ROLEs` configuration is appropriate for 112 MPI processes, and what would be the recommended parallelization settings for this TDDFT/ALDA calculation.
Should I use a different `X_CPU`, `X_ROLEs`, `PAR_def_mode`, or `X_nCPU_LinAlg_INV`?

Best regards,
Kartik Varshney
PhD, Physics
NISER, India