What's up in the land of the Linux kernel
summary
Kernel tree moves fast: ~13,500 commits per release with roughly 800k added and 500k removed lines, 5.4 is LTS, 5.5 merges a reworked crypto layer dubbed frankensync, and WireGuard support (5.6) lands in-tree; the PREEMPT_RT option exists since 5.3 but full RT needs lock/tick work and may slip to 5.7+. eBPF keeps expanding (tracing, XDP, networking), XFS gains reflink copy-on-write and online fsck, io_uring matures for high‑IO workloads, blk-iocost and USB4 drivers are scheduled, and Raspberry Pi/mainline graphics keep improving.
AI-written summary · about
chapters (40)
- 0:00Start
- 0:22quick orientation
- 1:065.5 under development release expected on February 3th (+/- one week)
- 2:44recent happenings
- 3:07ZOL breakage, big performance problem, block corruption bug, Code of Conduct & Linus break
- 5:22goal: improving & defragmenting kernel development workflow
- 6:20and no: kernel development won't move to gitlab or github :-
- 6:57Linus: "Don't use ZFS. It's that simple."
- 8:03no hope for a ZFS merge
- 10:29major happenings
- 12:09Realtime support soon to get mainlined RT-Tree/PREEMT_RT
- 13:38biggest missing part reworking printk
- 15:38BPF (aka eBPF) changing the #Linux kernel drastically one step at a time - and most people don't notice it
- 15:53BPF is a programmable VM in the kernel
- 21:08closing side note, as EOT: sadly, Realtime and BPF do not work together
- 23:59questions on the topics covered so far? #status, #COC, #workflow, #ZFS
- 27:58second part of the talk
- 28:08recent changes & WIP that are (1) useful/helpful day to day
- 32:08online fschk nearly stable, too
- 32:34exFAT support (5.4)
- 33:55virtio-fs (5.4)
- 34:05more efficient way to share host files or directories with a VM
- 34:31partly based on code from FUSE
- 34:45qemu support still WIP
- 36:48consider it, when writing new code that really needs I/O performance high throughput and/or low latencies
- 38:16Blkiocost (5.4) (formerly called lo. Weight)
- 39:20side note: move to cgroup2 finally happening after many years of preparation...
- 39:56USB4 support slated for 5.6
- 42:09support for AMD Radeon RX 5700 (Navi10) Linux 5.3 & Mesa 19.2
- 43:20WIP to support Intel Gen12 graphics (Tiger Lake & Xe) kemel and mesa
- 45:20Nouveau & all recent GPUs: unable to reach high speed or low power states distributable Firmware lacks support
- 46:42a new hope? Nvidia getting more open? let's wait and see...
- 46:57clang can build the kernel now on x86-64
- 47:39PSI Monitor (5.1) enhanced Pressure-stall Information (PSI), which was added in 4.20
- 48:25PSI Monitor allows better OOM handling prevent desktop shell from stalling
- 50:41currently it looks like: btrfs is better suited (and not as bad as its reputation)
- 50:57Multipath TCP
- 52:12support for Rapberry Pi 4 Linux 5.5/5.6
- 53:14Takeaways
- 53:44lot's of great improvements and better hardware support, too
