Intermittent vehicle motion on screen post upgrade (8.8.0 -> 8.9.0)

[jlumsden-mts]

Environment

• OS Version: Ubuntu 22.04 in WSL (Win11) with WSLg (NVIDIA MESA)
• Source or binary build?
  Binary 8.9.0 (following https://gazebosim.org/docs/harmonic/install_ubuntu/)

Description

• Expected behavior: Vehicle motion is smooth or at least updating multiple times per second. This was working fine in 8.8.0 but post upgrade to 8.9.0 seems to have regressed.

• Actual behavior: Despite a reasonable camera FPS and simulation speed (~400%) the vehicle itself is not updating on screen regularly - it only moves every few seconds - this was no the case before the update where it moved smoothly as you'd expect.

I don't believe anything else has changed here but I'm having trouble rolling back the installed package to 8.8.0 to verify this.

Steps to reproduce

1. This simulation is based on https://github.com/osrf/lrauv updated for Gazebo 8 (from 7)

1. Run "lrauv_control_demo.sdf" in examples/worlds

Output

The issue is difficult to describe in words, see this video for a better idea:
https://github.com/user-attachments/assets/5ece47bb-6198-4f08-a750-0184c70eb24c
https://github.com/user-attachments/assets/996e3bd4-1fab-47ae-8244-4cf56aa132ab

[jlumsden-mts]

Just to confirm DART physics is used with a step_size of 0.02 and real_time_factor of 0 as per:
https://github.com/osrf/lrauv/blob/main/lrauv_gazebo_plugins/worlds/tethys_at_portuguese_ledge.sdf.em#L75
I have tried some smaller step sizes (0.001) and it makes no difference - 0.02 was working OK previously in any case.

[jlumsden-mts]

For an easier reproduction I've run up the "lrauv_control_demo.sdf" in examples/worlds and I see the same behaviour where the vehicle position / pose is very slow to update on screen.

A short video of this here:
https://github.com/user-attachments/assets/996e3bd4-1fab-47ae-8244-4cf56aa132ab

[jlumsden-mts]

I've done some testing in WSL with 9.1.0 (using Ubuntu 24.04) and that does not exhibit this issue - everything updates smoothly.

[jlumsden-mts]

After reinstalling 22.04 (in WSL) from scratch this issue has gone away, unable to reproduce I'm chalking this up to an environment issue and closing this out.