Red Hat has released Fedora 33 beta, with the finished article expected at the end of this month, as well as version 7.9 of Red Hat Enterprise Linux.
Red Hat has two main Linux distributions – Fedora and Red Hat Enterprise Linux (RHEL) – as well as CentOS in its orbit. "Fedora is really the place that we take chances and risks and do all that important integration work between different components," said Mike McGrath, VP Linux engineering. "Assuming that we decide to go with them, they make their way to RHEL, either the next major release or in a minor release."
RHEL is the main commercial release, and CentOS a community-built release based on RHEL, in effect a non-commercial version.
Fedora is therefore always a good place to see what is coming next. What's new in 33? There is excellent documentation here. One notable change is that Btrfs is now the default file system for desktop editions. "Fedora tends to be more desktop and laptop focused, and RHEL to be more server focused," said McGrath.
The adoption of Btrfs was community driven, according to McGrath. Advantages include snapshotting, support for very large files, SSD awareness, deduplication, and background error correction. "We want to add new features, while reducing the amount of expertise needed to deal with situations like running out of disk space," say the notes. That said, the Btrfs wiki notes that the "code base is under heavy development". Fine for Fedora, but not ideal for RHEL, so it might be a while before this is the default there.
Fedora 33 also widens use of earlyOOM (Out of Memory) to the KDE version. This component automatically kills the largest process if free memory goes below a critical level. That is bad, but better than a completely frozen system. "Once you hit that OOM killer the system can be kind of unstable," said McGrath, emphasising that it is not a fix, but more a mitigation of an already bad scenario.
Another change is that Fedora 33 provides an IoT variant to an official Fedora edition. The challenge of IoT is not only that the OS needs to be lightweight (often it will run containers) but also that updates must be automated. Fedora IoT uses rpm-ostree to keep the OS up to date with the latest base OS image, plus additional packages as required. "The IoT edition had been incubating for a while, and we're promoting it to an Edition, which is slightly more official," said McGrath. "We're expecting to see a lot more adoption."
Fedora 33 also sees GNOME updated to 3.38 in the Workstation variant, improved thermal management, nano as the default editor, and updates to programming languages and runtimes, including the introduction of .NET Core on the ARM64 architecture. "We've had good luck with people using .NET," said McGrath, acknowledging Microsoft's progress in delivering open-source projects.
Why is Red Hat releasing a 7.9 update to RHEL, when version 8.2 is already available, and 8.3 in beta? This is the company's answer to the potential conflict between new features and compatibility.
"Starting with RHEL 8 we decided to have a more predictable release schedule," said McGrath. "Stability is very important in the enterprise, and when we release a RHEL 8 it's going to be supported for 10 years or longer." As new features come out over those 10 years, "it gets harder for us to attach those features to what was a very different computing time. So our solution has been to do a major release every three years and a minor release every six months. We need a place to put new and breaking features in, without disrupting the current install base. While we have some compatibility promises between [7 and 8], there are key features that are different, that if we had tried to put them into 7, they would definitely break and disrupt the user's workflow."
RHEL 7.0 came out in 2014. Is 7.9 the last major update? "I would love it to be. I sure hope it is," said McGrath.
McGrath also highlighted what he sees as a key feature across the RHEL family (though it can also be installed on other distributions), which is the Cockpit browser-based administration tool. "The reason I like this so much is because for someone that is coming from a Windows environment or not that familiar with Linux, this web console gives a great interface. It's one that I found even I'm comfortable with, even though I spend most of my time in the console."
Microsoft, of course, has moved to a similar solution with its Windows Admin Center, but in the opposite direction, from GUI desktop admin tools to the web browser. It looks like a consensus; and that will benefit Red Hat as it makes migration that little bit easier. ®