Run parallel job without hyperthreading Torque PBS script

Question

Is it possible to disable Hyperthreading? Or a way via torque PBS script to use only physical cores available in the node.

My problem is when I run my MPI job with node=1:ppn=12 it runs with a good speed.(1st iteration take less than 1min) but when I use node=2:ppn=12 the speed is horrible (1st iteration takes more than 6hrs)

My Torque PBS JOB SCRIPT

  #!/bin/bash
  #PBS -N Vcrlx
  #PBS -q batch
  #PBS -l nodes=2:ppn=12
  #PBS -l walltime=20:00:00
  #PBS -m bea
  #PBS -j oe 
cd $PBS_O_WORKDIR

mpirun -np 24 pw.x  < vcrlx.in > vcrlx.out

Tried solutions

I emailed them about this Hyperthreading problem but no response yet (10days)

As my code Quantum Espresso can run with MPI, OpenMP and with Mixed MPI+OpenMP. I tried my best to understand all these but failed to get desired results. Or maybe I misunderstood because of very poor background knowledge of these things.

I tried many combinations like following but none of them worked

  #!/bin/bash
  #PBS -N Vcrlx
  #PBS -q batch
  #PBS -l nodes=2:ppn=12::mpiprocs=1:ompthreads=24  <--------------
  #PBS -l walltime=24:00:00
  #PBS -m abe 
  #PBS -j oe 
cd $PBS_O_WORKDIR

mpirun -np 24 pw.x  < vcrlx.in > vcrlx.out

its output

     Parallel version (MPI & OpenMP), running on      48 processor cores
     Number of MPI processes:                24
     Threads/MPI process:                     2

     MPI processes distributed on     2 nodes
     R & G space division:  proc/nbgrp/npool/nimage =      24

Please help me to run the job without Hyperthreading. Thanks