Marco Compositor and VNC remote desktop Performance Issues

I've updated most of my desktops to Ubuntu Mate 20.04, but have hit a wall on upgrading my two work machines still running 18.04. Both of my work machines require a lot of remote desktop usage with VNC and I haven't been able to make Ubuntu Mate 20.04 work fast enough.

The issue comes down to the selected window manager. Marco (Adaptive compositor) works great for my local desktop, but is very slow for VNC remote desktop. In 18.04, Marco (No compositor) works fine, but in 20.04, there are some windows I'm not able to resize (like mate terminal.)

The most probably cause is that the theme I'm using, Adapta, hasn't been updated for the latest version of Mate, but works fine with Marco (Adaptive compositor) because of Mate's new magic. If I chose one of the included themes, it does work well enough (it's still hard to grab windows for resizing, but I don't think it's much worse than 18.04), but I like Adapta. So, my questions are:

  1. Does anyone know what part of a theme needs to be adjusted to resolve the issue of not being able to resize a window?
  2. The enhancements made to 20.04 for resizing windows no matter the theme is wonderful. Is it possible to port that behavior to Marco (No compositor?)
  3. Any work around to make Marco (Adaptive compositor) fast over VNC?

Even if you don't have an answer, thank you for taking the time to read my question.

1 Like

Hi :slight_smile:
If you use your machines as kind of jumphost, I can advise you to try apache guacamole :
This will let you remote control your machines with a web browser.
I'm using it and strongly advise it :slight_smile:

I got similar target and was unable to give to my machine more that 4Gb of RAM with 2 vCPU so i done some config :

  • I disabled Mate Animations in mate tweak that makes the machine run smoothly over VLC
  • Use a theme that is not so colorful - the one by default is just perfect
  • Disable wallpaper or set up a color one and not picture one
  • Do not use the plank dock
  • If possible, set up a screen resolution that is not too big
  • Wired access is much better than wireless one - good network is required

About the network :

  • Better to check all the wires to be sure you have cat 6, or cat 7 not to be blocked by a old wire
  • a good giga switch
  • network card that support 1Gb uplink

For apache guacamole :

  • Reconfigure VNC to listen only on (localhost) in order only guacamole to use it and the connection to be possible only over guacamole
  • 2FA auth with google auth :slight_smile:

For scaling, there is something I saw. If you boot your jumphost and login to GUI physically on the machine, this will make your resolution to be fixed to the screen size.
If you start the jumphost and leave it at login screen and next start vnc service via ssh, this will work better - you will be able to get the screen size adjusted to your web browser on client side.

I hope this will be helpful and I guess other community members will write here to help with their experience :slight_smile:

Thank you olek for your comprehensive reply. I've been doing more testing and the root of my issues are discussed in length in this other support request:

Basically it's a discussion on a theme's border being too small and the difficulty with mouse selection when using Marco (No compositor.) All of my testing of 20.04 with Marco (Adaptive compositor) has been on a local area network with a 10gbe connection. (If anybody wondered, I can't tell the difference between 1ge and 10gbe when running VNC on my home network.)

When comparing 18.04 to 20.04, there are definite changes in how Marco (No compositor) works. For example, I'm using a borderless theme (Adapta) and it's still usable (but not great) in 18.04. In 20.04, it's not usable at all - I can't resize windows - there's nothing to grab onto.

For a very fast VNC experience, Marco (No compositor) is the only way to go. I tried all the included themes and there are only about two that work OK with this setting. Those are Traditional Green and Traditional OK. It seems that all the other themes have very narrow borders and are hard to select. To solve the problem for now, I modified my third party theme I've been using (Adapta) by adding a 5 pixel theme border. It's not pretty, but it gets the job done for now.

Going forward, to keep the Mate desktop relevant for remote access needs, we need Marco (No compositor) to work like Marco (Adaptive compositor) does in handling detection of window borders for resizing.

BTW, I also checked out XFCE and they have exactly the same issues.