Previous article mentioned four of the most important yet most basic resources to monitor for the health of your JVM, but also of your system:

• CPU - high CPU usage affects your notebook by killing your battery. You need to hunt down that rogue browser tab or app that’s using most of your CPU, and kill it. It might be as ridiculous as Chrome animating a 16x16 gif
• disk - high disk usage affects speed with which your apps start or respond.
• memory - high memory usage increases swapping and may lead to apps being killed or your desktop grinding to halt.
• network - if apt or snap or something else suddenly decides to download 2GB worth of stuff while you’re on roaming/metered connection.

To easily monitor those in your Ubuntu desktop, you can install the System Monitor Extension which would then show itself permanently in the Gnome Shell Tray.

Note: this breaks on EVERY Ubuntu upgrade for me. Be prepared to live without it for a couple of weeks after Ubuntu upgrade.

Ubuntu 23.10

Of course TopHat stopped being ported to newer GNOME. Back to the trusty system-monitor-next. Install gnome-shell-extension-manager, run it and search for mgalgs (searching for system-monitor-next yields shitty unrelated results).

Make sure you have all the necessary dependencies installed:

sudo apt install gir1.2-gtop-2.0 gir1.2-nm-1.0 gir1.2-clutter-1.0 gnome-system-monitor

Ubuntu 23.04

Of course the fucking thing broke. I give up, I’m switching to TopHat. Install the gnome-shell-extension-manager via apt, then install the extension via the manager.

Don’t forget to sudo apt install gir1.2-gtop-2.0 as documented at TopHat Installation Guide.

Ubuntu 22.10

Install the gnome-shell-extension-manager via apt:

sudo apt install gnome-shell-extension-manager
extension-manager

You can now install extensions from the extension-manager itself: there are two tabs in the app, “Installed” and “Browse” and the latter one allows you to install extensions. Just search for “system monitor” and install system-monitor-next from mgalgs; make sure you have all the necessary dependencies installed:

sudo apt install gir1.2-gtop-2.0 gir1.2-nm-1.0 gir1.2-clutter-1.0 gnome-system-monitor

Ubuntu 22.04

Unfortunately the gnome-shell-extension-system-monitor deb package is no longer available from official repo at the moment. It needs to be installed as a Gnome extension.

The easiest way to manage extensions is to install the gnome-shell-extension-manager via apt:

sudo apt install gnome-shell-extension-manager
extension-manager

OR (but I hate that this would install chrome-gnome-shell)

sudo apt install gnome-shell-extension-prefs
gnome-extensions-app

Alternatively install the same thing via flatpak: org.gnome.Extensions flatpak, then run:

flatpak run org.gnome.Extensions

You can now install extensions from the extension-manager itself: there are two tabs in the app, “Installed” and “Browse” and the latter one allows you to install extensions. Just search for “system monitor” - the one from Cerin is the “official” one.

The “original” extension is not compatible with Gnome 42 at the moment, see+vote for #737. Workaround is to install system-monitor-next from mgalgs; make sure you have all the necessary dependencies installed:

sudo apt install gir1.2-gtop-2.0 gir1.2-nm-1.0 gir1.2-clutter-1.0 gnome-system-monitor

Workarounds

If you’ll get invalid language tag: C.UTF-8, then switch to a different language (C.UTF-8 didn’t work for me even though it was generated). Edit /etc/environment and add LANGUAGE=en_US.UTF-8. Then, run sudo locale-gen en_US en_US.UTF-8 and sudo dpkg-reconfigure locales and sudo update-locale LANG=en_US and reboot.

Ubuntu 21.10

There are two ways to have the extension installed:

• Via apt
• Via the official way of installing gnome extensions via Firefox

The official way

Firefox will install extensions from extensions.gnome.org. This will be done by using a Firefox extension, talking to your system via chrome-gnome-shell. Follow these steps:

1. Uninstall the extension deb package: sudo apt autoremove --purge gnome-shell-extension-system-monitor. Don’t worry, your settings will be preserved.
2. sudo apt install chrome-gnome-shell - this will allow to install and update extensions from your browser (yeah I don’t really like browser installing stuff into my system, but what can you do.)
3. Visit gnome-shell-system-monitor-applet and install all the necessary system packages as described by the page.
4. Visit https://extensions.gnome.org/extension/120/system-monitor/ and install the system-monitor gnome extension via Firefox. A Firefox extension is needed in order to install gnome extensions, the page will prompt you to install the plugin. You do not need to log in into the extensions.gnome.org website.
5. Download and enable the extension. The system monitor will be shown but the Preferences will fail to start, see+vote on Issue 704.
6. If the system monitor will fail to start and the local extensions page will show an ERROR next to the system-monitor add-on, simply logout and login again, or reboot your machine.

Warning: Firefox installed via snap (the default for Ubuntu 21.10) doesn’t support connections to ‘native host connector’ (chrome-gnome-shell), see+vote for Ubuntu bug #1741074. The only known workaround is to uninstall the Firefox snap and install the Firefox deb via:

1. sudo snap remove --purge firefox
2. sudo apt install firefox
3. sudo apt autoremove --purge lynx

then repeat the process above.

Going with the package

gnome-tweaks no longer manages gnome extensions starting from Ubuntu 21.10. Therefore, if you don’t have the extension already enabled when upgrading to Ubuntu 21.10, you will have to install a flatpak which manages gnome extensions as mentioned below.

Run

sudo apt install gnome-shell-extension-system-monitor

If the extension doesn’t activate itself, activate it either via

• org.gnome.Extensions flatpak
• or even simpler, sudo apt install gnome-shell-extension-prefs - the Settings will now allow you to enable/disable extensions.

In case of flatpak: Follow these guides to install flatpak on Ubuntu - it’s really easy. Then, run the app via

flatpak run org.gnome.Extensions

then make sure the system-monitor extension is enabled.

Ubuntu 21.04 and older

You can install install the extension via the browser, but I really hate browser installing stuff onto my machine, so I’ll use the old-fashioned apt command:

sudo apt install gnome-shell-extension-system-monitor

Log out, log in, the extension should auto-activate itself. If not, follow on.

Simply install the Gnome Tweaks:

sudo apt install gnome-tweaks

Then launch it, go to the Extensions tab and make sure that the System-monitor extension is activated.

Reporting Bugs

Since this extension literally breaks on every Ubuntu upgrade, it’s worth knowing how to report bugs.

1. type ubuntu-bug gnome-shell-extension-system-monitor into terminal, to report issues to Ubuntu bug tracker.
2. To see the stacktrace, type journalctl /usr/bin/gnome-shell -r and search for something like JS ERROR: Extension system-monitor@paradoxxx.zero.gmail.com. Paste that information into the bug report.