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doku:multimpi [2019/03/12 12:52]
jz
doku:multimpi [2023/03/14 12:53] (current)
goldenberg [VSC-3]
Line 3: Line 3:
 Sample job script to run two MPI tasks within one job script concurrently: Sample job script to run two MPI tasks within one job script concurrently:
  
-== With srun: == +==== VSC-4 =====
-<code> +
-#!/bin/bash +
-#SBATCH -J test +
-#SBATCH -N 1 +
-#SBATCH --ntasks-per-core=+
-#SBATCH --ntasks-per-node=2+
  
-export SLURM_STEP_GRES=none+Sample Job when for running multiple mpi jobs on a VSC-4 node. 
  
-module load intel/18 intel-mpi/2018+Note: The "mem_per_task" should be set such that
  
-for i in 0 8 +<code> 
-do +mem_per_task * mytasks < mem_per_node 2Gb
-  j=$(($i+1)) +
-  srun -n 2 --cpu_bind=map_cpu:$i,$j ./hello_world_intelmpi2018 & +
-done +
-wait +
- +
-exit 0+
 </code> </code>
  
-== With mpirun (Intel MPI): ==+The approx 2Gb reduction in available memory is due to operating system stored in memory. For a standard node with 96 Gb of Memory this would be eg.: 
 + 
 +<code> 
 +23 Gb * 4 92 Gb < 94 Gb 
 +</code>
  
 <code> <code>
 #!/bin/bash #!/bin/bash
-#SBATCH -J test+#SBATCH -J many
 #SBATCH -N 1 #SBATCH -N 1
-#SBATCH --ntasks-per-core=1 
-#SBATCH --ntasks-per-node=2 
  
 export SLURM_STEP_GRES=none export SLURM_STEP_GRES=none
  
-module load intel/18 intel-mpi/2018+mytasks=4 
 +cmd="stress -c 24" 
 +mem_per_task=10G
  
-for i in 0 8+for i in `seq 1 $mytasks`
 do do
-  j=$(($i+1)) +        srun --mem=$mem_per_task --cpus-per-task=--ntasks=1 $cmd &
-  mpirun -env I_MPI_PIN_PROCESSOR_LIST $i,$j -np ./hello_world_intelmpi2018 &+
 done done
 wait wait
  
-exit 0 
 </code> </code>
- 
-You can download the C code example here: {{ :doku:hello_world.c |hello_world.c}} 
-Compile it e.g. with: 
- 
-<code> 
-# module load intel/18 intel-mpi/2018 
-# mpiicc -lhwloc hello_world.c -o hello_world_intelmpi2018 
-<code> 
  
  
  • doku/multimpi.1552395162.txt.gz
  • Last modified: 2019/03/12 12:52
  • by jz