Liquorix Linux Kernel 7.1-18 lands with Project-C scheduler micro-optimizations
Liquorix 7.1-18 is out, tracking the Linux 7.1.10 base. Maintainer Steven Barrett, known as damentz, pushed two scheduler patches targeting an internal effort dubbed "Project-C." The goal is micro-optimization for the PDS/BMQ scheduler family.
Two patches landed in this release. The first replaces multiple conditional checks in sched_prio2idx() with a single range test, which cuts instruction count on the context switch hot path. The second strips an unlikely() compiler hint from the non-migratable task path. Profiling apparently showed non-migratable tasks are not rare in practice, especially with Liquorix's low-latency tuning. Hinting them as unlikely was throwing off the branch predictor.
What's in the update?
Project-C isn't officially documented anywhere outside the Liquorix ecosystem. It almost certainly refers to the ongoing work to refine the PDS/BMQ scheduler for better cache friendliness. The patches are consistent with that. You're looking at targeted fixes based on real workload profiling rather than speculative changes.
The internal version bumped to 7.1.10-3, which translates to v7.1.10-lqx3. The release cadence has been aggressive. Changelog entries show 7.1-15 through 7.1-18 stacked over four days in late August. That's a rapid turnaround. Barrett is using a Docker-based cross-compilation pipeline for Debian, Ubuntu, and Arch targets, though builds remain AMD64 only.
There are also some security changes lurking in the nearby commits. Lockdown LSM is enabled, Landlock made its way into the CONFIG_LSM list, and AppArmor is set as the default. These align with the zero-trust kernel direction in the 7.x series.
How to install
Liquorix ships prebuilt packages for Debian, Ubuntu, and Arch Linux. Barrett recommends this one-liner for a fresh install:
curl -s 'https://liquorix.net/install-liquorix.sh' | sudo bash
Keep in mind that this is a tuning release, not a feature dump. The kernel still carries Zen Interactive Tuning, hard kernel preemption, and a 1000 Hz tick rate. If you're chasing the last few milliseconds of latency for audio production or tighter frame times, Project-C is exactly the kind of work that matters. For the average desktop user, the difference will be imperceptible.
