# Why is pvserver using only one cpu ?

**URL:** https://discourse.paraview.org/t/why-is-pvserver-using-only-one-cpu/9355
**Category:** ParaView Support
**Tags:** mpi
**Created:** [April 5, 2022, 5:33am UTC](https://discourse.paraview.org/t/why-is-pvserver-using-only-one-cpu/9355 "2022-04-05T05:33:54Z")
**Posts on this page:** 1
**Page:** 1

<div class="post-metadata">

### Author: ![Nicholas\_Yue](https://discourse.paraview.org/user_avatar/discourse.paraview.org/nicholas_yue/32/5203_2.png) [@Nicholas\_Yue](https://discourse.paraview.org/u/Nicholas_Yue)
#### Post date: [April 5, 2022, 5:33am UTC](https://discourse.paraview.org/t/why-is-pvserver-using-only-one-cpu/9355/1 "2022-04-05T05:33:54Z")

</div>

I spun out a small 2 node MPI cluster on AWS to get familiar with Paraview in distributed mode.

Each node has 2 cores

From the head node, I ran the following command

```auto
/shared/ParaView-5.10.1-osmesa-MPI-Linux-Python3.9-x86_64/bin/mpiexec -hosts queue0-st-queue0-t2medium-2,queue0-st-queue0-t2medium-1 -np 2 /shared/ParaView-5.10.1-osmesa-MPI-Linux-Python3.9-x86_64/bin/pvserver

```

On the head node, I started paraview, connected to the pvserver and proceeded to load the head.vti dataset to exercise the MPI communication.

I enable the HUD to confirm that it was indeed performing remote/distributed rendering.

Running `top` on each of the compute node, I noticed that only one CPU in the compute node is being utilized.

Is this to be expected because of the way I started pvserver or is this due to me using VTI files for testing ?

Kind regards