I’ve sold my motorcycle some time ago, and I figured that at some point, I still wanted to write a long-term review about it. So here it is. The gearbox In my first blog about it, I praised the bike, and I stand by everything I wrote, but a few years have passed, and things … Continue reading "Multi-year review of the Softail Low Rider"
It’s been about a year since I got my motorcycle, and I figured it would be a good thing to write about it, and that now would be a good time to do it. I live in the suburbs of Paris, where public transports are probably the most popular way to travel in the region, … Continue reading "One year review of the Softail Low Rider"
I’m moving sceen.net to a smaller machine, and decided to shut down the Buildroot autobuilder that has been running on the server for more than 5 years now. Buildroot is a great project, with great people. I’ve been recommending it for more than a decade now, used it personally and professionally on multiple occasions, and … Continue reading "Shutting down the Buildroot autobuilder"
The project is still mostly stalled, unfortunately. But a couple of things were achieved : Simon Venken reported a bug on semaphores, which were reworked. Simon Venken also reported a bug concerning the chaining of wake-ups in sleep queues, which was fixed. the kern/mbuf module, providing message ring buffers, was added. the kern/log module was … Continue reading "X15 – Progress report – 2019Q1-2"
Beginner guides for astronomy often mention that binoculars are not only a good, cheap way to start, but also that they end up complementing a telescope acquired afterwards nicely. I got the telescope first, but I have to agree. And since my motorcycle recently became my main mode of transport, the relative lightness and compactness … Continue reading "Smaller is better"
How does a developer come up with code ? How does he know what to write, and if it’s a correct thing to do ? Spoiler alert: it’s much more art than science. Most developers have a rough idea of what their code has to do, and what results are considered valid, but it’s usually … Continue reading "Scenarios and invariants"
As a result of personal events, the project has been mostly stalled these last six months. However a few changes were made, the most important being : Interrupt handling rework on x86, with the merging of the trap module into the cpu module. Red zone support on x86 (amd64), which is required for full ABI … Continue reading "X15 – Progress report – 2018Q3-4"
Since I got myself an ARM Chromebook, I made it a goal to be able to work on X15 directly on that small device. This implies cross compiling from ARM (actually aarch64) to x86, and running it in an emulator. I used Crosstool-NG to generate two toolchains, available at http://ftp.sceen.net/ctng/aarch64/, and had to build QEMU from recent … Continue reading "Cross compiling X15 on ARM"
The major change of this quarter is the addition of a generic low level performance monitoring system, developed in large part by Rémy Noël. This system provides users with the ability to track low level events, such as cycles, instruction fetches or cache misses to name a few, either per-thread or per-processor. The implementation is … Continue reading "X15 – Progress report – 2018Q2"
It’s been a while since I’ve written about the progress on X15. As an open source project I work on in my free time, its development pace is unsurprisingly not constant, but despite that, a lot of progress was made since it was seriously restarted in 2017. Among the biggest changes are the new build … Continue reading "X15 – Progress report – 2018Q1"