Kernel News
Zack's Kernel News
This month in Kernel News: Shared Processes with Hyper-Threading; Cleaning Up printk(); and Rust in the Kernel.
Shared Processes with Hyper-Threading
Joel Fernandes wanted to speed up hyper-threading by making it possible for processes on the same CPU that trust each other to share hyper-threads. Hyper-threading is Intel's proprietary form of hardware-based multithreading. Generally in Linux and other operating systems (OSs), the OS is responsible for switching rapidly between processes, so everything on the system seems to be running at once. Hyper-threading does this at the hardware level, saving time for the OS. But the OS can still interact with Intel's hyper-threading features, so folks like Joel can try to eke out performance improvements.
Joel specifically wanted to improve Peter Zijlstra's "core-scheduling" patches, which Peter famously hates the way one hates slowly pulling out their own fingernails. He actually did this once. No, not really. However, the point of the core-scheduling patches is to make each CPU act like two. This way, for moments when one of the virtual CPUs has nothing to do, the other virtual CPU will keep chugging away, making sure the hardware "real" CPU is as fully utilized as possible.
Of course, processes running on those two hyper-threading virtual CPUs have to be treated like potential security threats, the same as all processes everywhere. If a hostile actor gets into a user process on a given system, the kernel wants to limit the amount of damage that actor can do. That's just part of standard Linux procedure. Keep everything isolated, and then nothing can hurt anything else too badly.
[...]
Buy this article as PDF
(incl. VAT)
Buy Linux Magazine
US / Canada
UK / Australia
Subscribe to our Linux Newsletters
Find Linux and Open Source Jobs
Subscribe to our ADMIN Newsletters
Support Our Work
Linux Magazine content is made possible with support from readers like you. Please consider contributing when you’ve found an article to be beneficial.
News
-
TuxCare Announces Support for AlmaLinux 9.2
Thanks to TuxCare, AlmaLinux 9.2 (and soon version 9.6) now enjoys years of ongoing patching and compliance.
-
Go-Based Botnet Attacking IoT Devices
Using an SSH credential brute-force attack, the Go-based PumaBot is exploiting IoT devices everywhere.
-
Plasma 6.5 Promises Better Memory Optimization
With the stable Plasma 6.4 on the horizon, KDE has a few new tricks up its sleeve for Plasma 6.5.
-
KaOS 2025.05 Officially Qt5 Free
If you're a fan of independent Linux distributions, the team behind KaOS is proud to announce the latest iteration that includes kernel 6.14 and KDE's Plasma 6.3.5.
-
Linux Kernel 6.15 Now Available
The latest Linux kernel is now available with several new features/improvements and the usual bug fixes.
-
Microsoft Makes Surprising WSL Announcement
In a move that might surprise some users, Microsoft has made Windows Subsystem for Linux open source.
-
Red Hat Releases RHEL 10 Early
Red Hat quietly rolled out the official release of RHEL 10.0 a bit early.
-
openSUSE Joins End of 10
openSUSE has decided to not only join the End of 10 movement but it also will no longer support the Deepin Desktop Environment.
-
New Version of Flatpak Released
Flatpak 1.16.1 is now available as the latest, stable version with various improvements.
-
IBM Announces Powerhouse Linux Server
IBM has unleashed a seriously powerful Linux server with the LinuxONE Emperor 5.