OS News Archive

Not the most detailed description just yet, but Fuchsia seems to be getting fleshed out more and more.

It's one of many, for sure, but as far as I'm concerned, we can never have enough of them: experimental hobby operating systems. GopherOS - no, not what you think - is an experimental operating system written in Go, licensed under the MIT license. It's all very small and early, but possibly interesting to some of you.

With the new version 17.05, the Genode project moves forward to the goal of becoming more attractive and approachable to a wider audience. On the one hand, the release promises to be a sustainable basis for longer-term projects. With a modern tool chain based on GCC 6.3, Qt 5.8, VirtualBox 5.2.11, and the framework's finished API modernization, the foreseeable future will be free of disruptions for users. On the other hand, Genode introduced a new approach and tooling for package management to relieve users from low-level technicalities.

Modern operating systems are unthinkable without a package-management solution for installing and updating software. Until now, however, Genode's work flows were primarily geared towards appliance-like systems that come in the shape of system images. Even though the Genode developers managed to build a day-to-day usable OS (called "Turmvilla") for their own use on that basis, there is a natural limit of how scalable such systems can be. Even for the developers, installing and updating such a system is a burden. Instead up building and installing a new system image on each update, users universally expect to install software from ready-to-use packages, and to update and configure the system in parts instead of a whole.

The discussion of suitable package-management approaches for Genode reaches several years back. The first step in this direction were custom tools for managing and integrating 3rd-party source code with the framework. But there was no notion of pre-built and easy-to-install packages, nor even a tangible idea of what a package in the context of Genode should represent. During a long period of experimentation, the developers encountered and fell in love with the Nix package manager. This encounter was followed by porting work, mind-bending architectural discussions, and a series of prototype scenarios. However, while those prototypes were technically sophisticated and interesting playgrounds, they were also complicated. A real-world solution remained cloudy.

At one time, it became clear that the universal notions of "software packages" and the role of a package manager made things more complicated than they should be. After all, Nix is designed for Unix-like systems with its existing ecosystem of libraries, build tools, conventions, and methodologies. In contrast, Genode opens up unique opportunities for simplification thanks to its breath of scope that covers the entire software stack including the build system, tool chain, the ABI and API design, the inter-component protocols, the dynamic linker, the system configuration, and the execution runtime. By taking a step back and soul-searching for the actual problem to solve, a strikingly simple new approach emerged. It is undeniably inspired by the virtues of Nix. But it leverages Genode in ways that wouldn't be possible with a ported version of Nix. For example, it facilitates Genode's notion of library ABIs to largely decouple libraries from applications and thereby completely eliminates transitive build-time dependencies. Or as another example, by introducing sensible categories of packaged content, the need for a package description language disappeared.

Genode's release 17.05 contains the new packaging tools. Even though they are still labeled as experimental, the release comes with several examples of modest system scenarios based on them. Other prominent news are a feature-complete version of VirtualBox 5 for the NOVA microkernel, the update of Qt to version 5.8, added support for the Nim programming language, a new tool chain based on GCC 6.3 including Ada support, new tools for monitoring network traffic and CPU load, greatly enhanced flexibility of the init component, and a brand new timeout API. All these topics are covered in detail by the release documentation.

I'm starting to sound like a broken record on this topic, but it can't be said often enough: the preservation of software - whether important world-changing or not - is crucial if we want to document the history of where software came from, and where it's going to.

Raise your hand if you're surprised.

Development is continuing at a steady pace.

Fascinating story with tons of details, definitely a must-read. Interestingly enough - or sadly enough - I can't seem to find a whole lot of information on the MERA 400 in English, and since I don't speak or read Polish, I can't really give much more information than you can find in the source article. There is a Wikipedia page on the MERA 400's progenitor, the K-202.

The just released version 17.02 of the Genode OS framework comes with greatly enhanced virtual file-system capabilities, eases the creation of dynamic system compositions, and adds a new facility for processing user input. Furthermore, the components have become binary-compatible across kernel boundaries by default such that entire system scenarios can be moved from one kernel to another without recompiling the components.

Genode's virtual file-system (VFS) infrastructure has a twisted history. Originally created as a necessity for enabling command-line-based GNU programs to run within Genode's custom Unix runtime, the VFS was later extracted as a separate library. This library eventually became an optional and later intrinsic part of Genode's C runtime. It also happened to become the basis of a file-system-server component. If this sounds a bit confusing, it probably is. But the resulting design takes the notion of virtual file systems to an new level.

First, instead of providing a system-wide VFS like Unix does, in Genode each component can have its own VFS. Technically, it is a library that turns a number of Genode sessions into a file-system representation according the component's configuration. Via those sessions, the component is able to access services provided by other components such as file systems, terminals, or block devices. Furthermore, several built-in file systems are provided locally from within the component. Since the VFS is local to each component, the view of the component's world can be shaped by its parent in arbitrary ways.

By default, each component runs in isolation. Whenever two components are meant to share a certain part of their VFS with one another, both mount a file-system session of the same server into their local VFS. This sharing is a deliberate decision by the component's common parent and thereby subjected to the parent's security policy. One particularly interesting file-system server is the so-called VFS server. It uses an arbitrarily configured VFS internally and exports its content as a file-system service, which can then be mounted in other components. This way, the VFS server can be used to emulate a "global" VFS, or to multiplex access to any file-system types supported by the VFS.

Speaking of supported file-system types, this is where the VFS becomes literally infinitely flexible. The VFS features a plugin interface that incorporates file system types provided in the form of shared libraries. If the VFS configuration refers to a file system type not known by the VFS, a corresponding plugin is loaded. For example, there exists a plugin for generating random numbers based of the jitter of CPU execution time. The file system, when mounted, hosts only a single read-only file that produces random numbers. But VFS plugins can become much more creative. Via the rump-kernel VFS plugin, one can incorporate the file systems of the NetBSD kernel into any VFS-using component. Genode 17.02 furthermore comes with a Plan-9-inspired VFS plugin that makes the Linux TCP/IP stack available as a file system. The C runtime then translates BSD-socket API calls to file-system operations on the socket file system, which, in turn, are handled by the Linux TCP/IP stack. The fascinating part is that this all happens within a single component. Such a component is in fact quite similar to a unikernel.

If two applications ought to share the same TCP/IP stack, the VFS server comes in handy. The Linux TCP/IP stack is then mounted once in the VFS server, which, in turn, provides file-system sessions to the applications. Each application then accesses the TCP/IP stack indirectly through those file-system sessions. In this scenario, the VFS server suddenly becomes a network multiplexer.

The VFS is not the only topic of the current release. Another highlight is the introduction of a application binary interface that makes all components binary compatible across kernel boundaries by default. Combined with the new kernel-independent build directories, it has become possible to move complete system scenarios from kernels as different as L4, NOVA, seL4, or Linux in matter of seconds. Further improvements of Genode 17.02 are the addition of a generic input-event processor, new SD-card drivers, the update to the version 0.8 of the Muen separation kernel, and a new mechanism for managing dynamic subsystems. All the improvements are described in detail in the release documentation.

ToaruOS 1.0 was released 18 days ago, and since then, several bugfix releases have been released. The latest release - the one you want to test - is 1.0.3.

IT's a remarkably fun operating system, and runs without any problems in VirtualBox. I've played with it a bit during the day, messing around with the basic but elegantly simple UI, browsing the file system, installing a few packages through the graphical package manager, and playing some Quake. It's rare for hobby operating systems to achieve this level of functionality in a 1.0 release, so colour me pleasantly surprised.

The code's on github.

The Z88 Development Team has released a new version of the system ROM for the Cambridge Z88 portable.

The team also outlines its plans for the future:

Open source, custom educational operating system. The first public alpha release is out.

Jehanne is a new distributed operating system designed for programmers. The core values that lead the development are simplicity and security. Jehanne is a fork of Harvey (which in turn is a fork of Plan 9 from Bell Labs merged with Nix's kernel sources) but diverges from the design and conventions of its ancestors whenever they are at odds with its goals. Read about development progress made in 2016.

The code is very approachable for anyone interested in capability-based microkernel design.