And my Kernel Recipes talk is now available: https://youtu.be/qYPCL1KGdQA

A big "Thank you!" to everyone involved!

And here is the video of mine: https://youtu.be/lvRuBxli_yU?si=iybBRdrINHydfSjb

Thank you @KernelRecipes !

#linux #kernel #damon #kr2025

RE: https://fosstodon.org/@KernelRecipes/115335044360364512

After letting them simmer for a few days, they’re finally ready! The #kr2025 videos are now online and waiting for you to watch. You’ll also find the presentation slides we’ve received so far.

Enjoy!

Slides and videos: https://kernel-recipes.org/en/2025/schedule/

Watch all the videos : https://www.youtube.com/playlist?list=PLQ8PmP_dnN7JIsjWbFPeRdze4MQHHkIm8

The next Portland Linux Kernel Meetup has been scheduled for Oct 16th!

Hope to see folks there!

https://ikluft.github.io/pdx-lkmu/october-2025-portland-linux-kernel-meetup.html

Linux kernel memory mangement subsystem changes [1] for 6.18-rc1, which includes most new features, are merged into the mainline.

So many interesting works in there. To DAMON maintainer's humble view, two brilliant changes stand out.

1. virtual address space page level monitoring support [2], which was developed by Yueyang Pan (Meta).
2. Support of 32-bit ARM with LPAE [3], which was collaboratively developed by I and Huawei people (Quanmin Yan and Ze Zuo). Most changes are authored by me, but the real workers were Quanmin and Ze from Huawei.

As always I highly recommend everyone to read Andrew's great summary [1] of the whole changes!

[1] https://lore.kernel.org/20251001190218.f33f695b869696c2df9e841d@linux-foundation.org
[2] https://lkml.kernel.org/r/cover.1754135312.git.pyyjason@gmail.com
[3] https://lore.kernel.org/https://lkml.kernel.org/r/20250828171242.59810-1-sj@kernel.org

#linux #kernel #mm #damon #6.18-rc1 #pull_request

Benchmarking the different machines in my office with the wonderful kcbench: http://www.kroah.com/log/blog/2025/10/01/the-only-benchmark-that-matters-is.../

Linus removed #bcachefs from mainline, it thus will be gone as of #Linux 6.18:

https://git.kernel.org/torvalds/c/f2c61db29f277b9c80de92102fc532cc247495cd

""bcachefs was marked 'externally maintained' in 6.17 but the code remained to make the transition smoother.

It's now a DKMS module, making the in-kernel code stale, so remove it to avoid any version confusion.""

284 files changed, 0 insertions, 117483 deletions

#kernel #LinuxKernel

According to LWN, I was [1] 14-th most active developer for Linux v6.17, in terms of the number of changes. Numbers are no more no less just numbers, but being listed there twice [2] means something to me :)

[1] https://lwn.net/Articles/1038358/
[2] https://social.kernel.org/notice/AsT2MVtG6Lv7PONehE

#linux #kernel #damon #lwn

I'm happy to share that a few of my talk proposals for LPC and OSSummit Japan, which will be held in the second week of December, are accepted.

In OSSummit Japan, I will introduce [1] 'hkml', the mail management tool for Linux kernel development.

In the Refereed track of LPC, I will introduce new DAMON features for page level and fleet wide data access monitoring.

In the "Device and Specific Purpose Memory" micro conference of LPC, I will discuss a plan for utilizing DAMON for access-aware page migrations on general NUMA systems including those for CXL, CPU, GPU and any processors.

In the "Linux System Monitoring and Observability" micro conference of LPC, I will share history and limitations on DAMON's output visualization formats and discuss how we can improve.

[1] https://sched.co/29FmF

#linux #kernel #damon #hkml #ossummit #LinuxPlumbers

I got my first DAMON t-shirt.

You might need to zoom-in to see why I'm saying it is a DAMON t-shirt, like you may need to zoom in/out DAMON-generated access pattern heatmaps, e.g., 'damo report heatmap --interactive_edit'[1].

[1] https://github.com/damonitor/damo/blob/next/USAGE.md#heatmap-scoping

#linux #kernel #damon #t-shirt

@KernelRecipes It was an honor to give a talk at kernel recipe, and getting so many grateful questions and discussions about DAMON during and after the talk. The slides are available at https://github.com/damonitor/talks/tree/master/2025/kernel_recipes

#linux #kernel #damon #kr2025

RE: https://fosstodon.org/@KernelRecipes/115253831274830187

@sj on stage about memory: Overcoming Observer Effects in Memory Management with DAMON

https://kernel-recipes.org/en/2025/schedule/overcoming-observer-effects-in-memory-management-with-damon/

#kr2025

@sj DAMON has been upstream in Linux 5.15. Main goal is to have something like a space-time view
#kr2025

Kangrejos was awesome. I'm now in Paris for presenting [1] DAMON at Kernel Recipes, Tuesday.

[1] https://kernel-recipes.org/en/2025/schedule/overcoming-observer-effects-in-memory-management-with-damon/

#kangrejos #kernelrecipes

RE: https://social.kernel.org/objects/7f1cced2-39e6-4a15-8b0a-ba3cf3b3955b

In 2023, I walked [1] on the France route of Camino de Santiago from Burgos to Santiago de Compostela (~500 km) to prepare (walk on days, work on slides and code on nights) for DAMON talk [2] at OSSummit Europe. This year, I walked it again from Saint Jean Pied de Port to Burgos to complete the route, and further from Burgos to Carrion de los condes (~322 km) to prepare for Kangjeros [3] and Kernel Recipes [4]. Now I’m ready to attend talks and made a first draft [5] of my Kernel Recipes talk slides. Switching from a pilgrim to a conference attendee and heading to Kangrejos now. Looking forward to meeting people on Kangrejos and Kernel Recipes!

[1] https://social.kernel.org/notice/AZrKdcNdDyaDwkShou
[2] https://static.sched.com/hosted_files/osseu2023/92/damo_ossummit_eu_2023.pdf
[3] https://kangrejos.com/
[4] https://kernel-recipes.org/en/2025/schedule/overcoming-observer-effects-in-memory-management-with-damon/
[5] https://github.com/damonitor/talks/blob/master/2025/kernel_recipes/damon_kernel_recipes2025.pdf

#kangjeros #kernelrecipes #caminodesantiago

Linux Plumbers 2025 in Tokyo’s Call for Proposals is nearing its end! https://lpc.events/blog/current/index.php/2025/09/08/the-call-for-proposals-is-nearing-its-end/

Today is my last day at Meta. This has been the best team I’ve ever been on, and I’ve been on some great teams. Next week I start a new chapter, I will be joining Anthropic to help them scale out their infrastructure and put my decades of kernel and systems experience to use. I will be stepping back from kernel development as my primary job for the first time in my career. I’m sad to leave my colleagues, but I’m excited to try something new and see where it takes me.

A patch series[1] for making DAMON supports ARM (32bit) with LPAE has just landed on mm-new tree. It was made by a great and joyful collaboration between I and Huawei (Quanmin Yan and Zuo Ze). Hopefully this will land on Linux v6.18.

[1] https://lkml.kernel.org/r/20250822093420.2103803-2-yanquanmin1@huawei.com

#linux #kernel #damon

Looks like the @opensuse Tumbleweed kernel will soon (when 6.17 is final and passes QA) produce a warning when mounting a bcachefs instance... https://bugzilla.opensuse.org/show_bug.cgi?id=1248109

DAMON results are arguably hard to understand. And no single visualization fits all. Hence DAMON user-space tool provides a feature[1] that lets users program their own visualization in Python code.

A visualization recently suggested was showing size of memory for different hotness, and sort the size values by the hotness. It can intuitively show cold memory tail. We implemented it as another custom visualization program[2].

The script outputs the visualization in text format, that can easily be plotted as a chart, like attaching.

[1] https://github.com/damonitor/damo/blob/next/USAGE.md#damo-report-access-programming-visualization
[2] https://github.com/damonitor/damo/blob/next/report_access_exec_scripts/idle_time_mem_sz.py

#linux #kernel #damon #damo