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today's leftovers

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  • Tableview performance

    In my previous blog post, I wrote about the new TableView for Qt-5.12. What I didn’t mention was how the new TableView performs compared to the old TableView in QtQuick Controls 1. However, the old version had some serious performance issues, which is what led us to implement a new one from scratch. The reason for the bad performance comes from the fact that it’s written on top of ListView. But ListView is designed and optimized to show only one column, which of course is problematic when you try to use it to show a table with multiple columns.

    To work around this limitation, the old TableView implements a little hack: it takes each column delegate and puts them side-by-side to create one fat row delegate. From ListViews point of view, it looks like a normal list delegate. The result is that whenever a new row is flicked in, all the items inside that delegate (which is one item for each column) will be instantiated in one go. Although this is not a disaster for a table with only a handfull of columns, performance takes a major hit when a table is of a non-trivial size. And to be fair, the old TableView was never designed to handle anything else. But for tables where you have, lets say, hundred columns or more, you will create hundred new items for each row flicked in. And most of them ends up hidden outside the viewport. And that is actually the best case; a delegate is normally composed of many items, so the item count will be even higher. The video underneath shows how scrolling can grind to a halt when using a model with only thirty columns.

  • QmlBook gets CI/CD

    Christmas is coming and a long and exciting fall is coming to and end. One of my projects during this fall has been to update the QmlBook. This was made possible by The Qt Company who generously stepped in and sponsored my work on this – thank you all!

    I’ve worked away during the fall adding a whole bunch of new contents and the documentation people over at The Qt Company has joined in and helped with a language review. One frustrating aspect of the QmlBook project has unfortunately been that the CI/CD system has been broken for a very long time. This means that even the small typo fixes made over the past months has not made it beyond the source git repository.

  • GUADEC 2018 - Product Management In Open Source

    This year at GUADEC in Almería I was lucky enough to give a talk entitled “Product Management in Open Source”. I’ll give a text synopsis of the talk below but if you prefer you can watch the whole thing as delivered at the Internet Archive or have a look at the slides, which are entirely mysterious when viewed alone:

    The talk begins like so: I’m Nick Richards. I’ve been a GNOME User for 20 years and a contributor and Foundation Member - 10 years (off and on). These days, the Free Software project I’m most passionate about is Flathub.

    These days I’m a Product Manager at Endless. Endless OS ships a customised, forked version of GNOME shell and a plain version of the rest of the GNOME platform. It’s currently based on 3.26 but with plenty of activity going on upstream.

  • Archman 2018.12 JWM Screenshot Tour
  • ArchLabs Linux 2018.12.17 overview

    In this video, I am going to show an overview of ArchLabs Linux 2018.12.17 and some of the applications pre-installed.

More in Tux Machines

digiKam 7.7.0 is released

After three months of active maintenance and another bug triage, the digiKam team is proud to present version 7.7.0 of its open source digital photo manager. See below the list of most important features coming with this release. Read more

Dilution and Misuse of the "Linux" Brand

Samsung, Red Hat to Work on Linux Drivers for Future Tech

The metaverse is expected to uproot system design as we know it, and Samsung is one of many hardware vendors re-imagining data center infrastructure in preparation for a parallel 3D world. Samsung is working on new memory technologies that provide faster bandwidth inside hardware for data to travel between CPUs, storage and other computing resources. The company also announced it was partnering with Red Hat to ensure these technologies have Linux compatibility. Read more

today's howtos

  • How to install go1.19beta on Ubuntu 22.04 – NextGenTips

    In this tutorial, we are going to explore how to install go on Ubuntu 22.04 Golang is an open-source programming language that is easy to learn and use. It is built-in concurrency and has a robust standard library. It is reliable, builds fast, and efficient software that scales fast. Its concurrency mechanisms make it easy to write programs that get the most out of multicore and networked machines, while its novel-type systems enable flexible and modular program constructions. Go compiles quickly to machine code and has the convenience of garbage collection and the power of run-time reflection. In this guide, we are going to learn how to install golang 1.19beta on Ubuntu 22.04. Go 1.19beta1 is not yet released. There is so much work in progress with all the documentation.

  • molecule test: failed to connect to bus in systemd container - openQA bites

    Ansible Molecule is a project to help you test your ansible roles. I’m using molecule for automatically testing the ansible roles of geekoops.

  • How To Install MongoDB on AlmaLinux 9 - idroot

    In this tutorial, we will show you how to install MongoDB on AlmaLinux 9. For those of you who didn’t know, MongoDB is a high-performance, highly scalable document-oriented NoSQL database. Unlike in SQL databases where data is stored in rows and columns inside tables, in MongoDB, data is structured in JSON-like format inside records which are referred to as documents. The open-source attribute of MongoDB as a database software makes it an ideal candidate for almost any database-related project. This article assumes you have at least basic knowledge of Linux, know how to use the shell, and most importantly, you host your site on your own VPS. The installation is quite simple and assumes you are running in the root account, if not you may need to add ‘sudo‘ to the commands to get root privileges. I will show you the step-by-step installation of the MongoDB NoSQL database on AlmaLinux 9. You can follow the same instructions for CentOS and Rocky Linux.

  • An introduction (and how-to) to Plugin Loader for the Steam Deck. - Invidious
  • Self-host a Ghost Blog With Traefik

    Ghost is a very popular open-source content management system. Started as an alternative to WordPress and it went on to become an alternative to Substack by focusing on membership and newsletter. The creators of Ghost offer managed Pro hosting but it may not fit everyone's budget. Alternatively, you can self-host it on your own cloud servers. On Linux handbook, we already have a guide on deploying Ghost with Docker in a reverse proxy setup. Instead of Ngnix reverse proxy, you can also use another software called Traefik with Docker. It is a popular open-source cloud-native application proxy, API Gateway, Edge-router, and more. I use Traefik to secure my websites using an SSL certificate obtained from Let's Encrypt. Once deployed, Traefik can automatically manage your certificates and their renewals. In this tutorial, I'll share the necessary steps for deploying a Ghost blog with Docker and Traefik.