In this quick guide, I will show how you can adjust the color temperature of your screen in Ubuntu using the terminal. No additional GUI installation is required and you can enjoy the night light even if your desktop environment doesn't provide a native one.

• The Art of (Not) Painting Pixels – GNOME Shell & Mutter

  Being a compositor and a compositing window manager, the most important aspect Mutter and GNOME Shell is to paint pixels to your monitors with relevant content. A large part of this content is provided by applications themselves, but many elements still need to be rendered on top of them.

  Over the past few years, Mutter’s codebase has slowly but steadily been refactored, cleaned up, reorganized, and modernized. This includes the internal copies of Clutter and Cogl. With the beginning of the GNOME 40 development cycle, it all converged in a specially large and exciting set of changes which we’ll be talking about in this article.

• GSoD Weekly Summary 5

  Before starting this week, I created an issue mentioning all the issues that I found and started completing them one by one while I kept adding new ones when required. So now the second task was to look again for the next issue which I found under “Using the Keyboard” there was a link missing which I added in the documentation.

  After this, the next task was to fix the subscript and superscript page style and add a link to it too. These changes I included with my previous PR.

• Ubuntu Fridge | Call for nominations for the Local Communities Council

  The Local Communities (LoCo) Council has been vacant for some time and has not been restaffed due to a vacant Community Council. Since the Community Council has now been newly elected, a nomination for the LoCo Council is now being announced.

  The LoCo Council is a board of people who are in charge of empowering and helping out LoCo Teams worldwide. Their members have two-year terms, and we have seven open seats at the Council.

• Canonical Drops etcd for Dqlite For MicroK8s

  MicroK8s is a lightweight and easy to use Kubernetes distribution designed to run in resource-constrained environments such as IoT and edge devices. As Canonical is eyeing enterprise use-cases it’s making Microk8s more resilient by adding high availability capabilities to it.

  Microk8s already has the clustering feature; with a single command, users can join multiple MicroK8s nodes in a cluster. With HA, as soon as users join three or more nodes, they get the Kubernetes control plane distributed across these nodes. If they join more nodes they get all the API services of Kubernetes available on all nodes and the control plane is still distributed on these nodes.

At the core of the emerging foundation that is Ubuntu Appliances is the aptly named Ubuntu Core, a slimmed-down Ubuntu operating system crafted with the IoT use case in mind. What distinguishes Ubuntu Core, which users can run as a standalone, and Ubuntu Appliances, is that each appliance comes preloaded with a featured service, and all the necessary programs are installed and managed via the Snaps containerized installation mechanism.

With this structure, appliances are designed to just work “out of the box,” if we borrow that brick-and-mortar paradigm in the sense of post-flashing, post-booting, and post-configuration. Users will need to boot the appliance device and perform a token amount of local administration, provide it with an Internet connection with a static LAN IP address, and set up an Ubuntu One account if they don’t have one. A few web GUI prompts later, and the user is up and running.

Ubuntu then does the rest, and that encompasses a lot of heavy lifting. Appliances will update themselves for a 10-year lifespan as long as they have Internet access. If all goes according to plan, users shouldn’t have to give a second thought to their appliance unless they want to change its configuration. Even then, all they have to do is enter the Web administration GUI, toggle a few switches, and close the tab.

Security and performance are often mutually exclusive concepts. A great user experience is one that manages to blend the two in a way that does not compromise on robust, solid foundations of security on one hand, and a fast, responsive software interaction on the other.

Snaps are self-contained applications, with layered security, and as a result, sometimes, they may have reduced perceived performance compared to those same applications offered via traditional Linux packaging mechanisms. We are well aware of this phenomenon, and we have invested significant effort and time in resolving any speed gaps, while keeping security in mind. Last year, we talked about improved snap startup times following fontconfig cache optimization. Now, we want to tell you about another major milestone – the use of a new compression algorithm for snaps offers 2-3x improvement in application startup times!

LZO and XZ algorithms

By default, snaps are packaged as a compressed, read-only squashfs filesystem using the XZ algorithm. This results in a high level of compression but consequently requires more processing power to uncompress and expand the filesystem for use. On the desktops, users may perceive this as a “slowness” – the time it takes for the application to launch. This is also far more noticeable on first launch only, before the application data is cached in memory. Subsequent launches are fast and typically, there’s little to no difference compared to traditionally packaged applications.

To improve startup times, we decided to test a different algorithm – LZO – which offers lesser compression, but needs less processing power to complete the action.

As a test case, we chose the Chromium browser (stable build, 85.X). We believe this is a highly representative case, for several reasons. One, the browser is a ubiquitous (and popular) application, with frequent usage, so any potential slowness is likely to be noticeable. Two, Chromium is a relatively large and complex application. Three, it is not part of any specific Linux desktop environment, which makes the testing independent and accurate.

For comparison, the XZ-compressed snap weighs ~150 MB, whereas the one using the LZO compression is ~250 MB in size.