I'll travel Denver next week for DAMON talk at Open Source Summit North America. If you have any topic for in-person DAMON beer/coffee/tea chat, please reach out to me! https://lore.kernel.org/20250620204743.98321-1-sj@kernel.org

#linux #kernel #damon #ossna

RE: https://social.kernel.org/objects/c5a2bd49-eb02-4dbe-a1f1-00dd85f4b512

A new DAMON user-space tool feature of today is drawing heatmap after sorting regions on the space by their access temperature.

The feature can be used with 'damo report heatmap --sort_temperature'. The access temperature calculation can be customized using '--temperature_weights'.

Attaching heatmps of a DAMON-snapshot and a DAMON-record, for unsorted and sorted heatmaps.

#linux #kernel #damon #damo

Intel has published another excellent ArXiv paper[1] for memory tiering. The research used DAMON for a validation of the behavior of their approach (GPAC).

[1] https://arxiv.org/pdf/2506.06067

#linux #kernel #damon

I use 'masim' for testing DAMON against artificial access patterns. I recently started thinking it might be useful for not only DAMON but also other memory management systems that I have interest, such as memory tiering and compressions. So I finally got a time to document its configuration format[1], about 7 years after its first release.

[1] https://github.com/sjp38/masim/blob/master/README.md

#linux #kernel #damon #masim

Linus Torvalds Rejects The Idea Of Enabling DAMON By Default In The Linux Kernel

DAMON is a nifty data access monitoring solution for the Linux kernel developed by Amazon and other parties for system monitoring and performance/efficiency optimizations and more. But it's not so ground-breaking that it's worth enabling by default in all Linux kernel builds, Linus Torvalds has decided...
https://www.phoronix.com/news/Linux-DAMON-By-Default-No

Ticket sales for Kernel Recipes 2025 are now open! The conference will take place from September 22 to 24, 2025, in Paris. The agenda is still in the works, but you can already check out the list of speakers and a few of the topics online.

https://kernel-recipes.org/en/2025/

If you're a student, we’re offering a 50% discount—just get in touch with us!

See you in september!

Like everybody else, LWN is affected by the current turbulence in the political and economic spheres; we expect to get through this period, but there will be some challenges.

To put it bluntly: starting around the beginning of March, we have observed a distinct drop in both new subscriptions and renewals. [...] #OpenSource #Linux #LWN

https://lwn.net/Articles/1019217/

DAMON user-space tool's heatmap visualization has recently advanced. I wrote more details on the blog: https://damonitor.github.io/posts/damo_heatmap_modernization_2025_06/

#linux #kernel #damon #damo

Changes for enabling CONFIG_DAMON by default[1] have just merged[2] into the mainline, by the second MM subsystem pull request for Linux 6.16-rc1. This will help DAMON be better tested and easier to be used.

[1] https://lore.kernel.org/all/20250521042755.39653-1-sj@kernel.org/
[2] https://lore.kernel.org/all/174891081008.961800.5493448222601669134.pr-tracker-bot@kernel.org/

#linux #kernel #damon

Andrew Morton posted an MM pull request[1] for Linux 6.16-rc1, and it is now merged into the mainline. It includes many interesting changes including DAMON patches[2] for more self-driven memory tiering.

[1] https://lore.kernel.org/all/20250531145342.383090aa5ed5bcefee0740d5@linux-foundation.org/
[2] https://lore.kernel.org/all/20250420194030.75838-1-sj@kernel.org/

#linux #kernel #damon #mm #pullrequest

Thanks Meta (and of course @paulmckrcu and @axboe for joining the game once more in Kernel Recipes 2025! Thanks for keeping this event open and affordable.

We are still missing some sponsors. You can also join. Have a look here:
https://kernel-recipes.org/en/2025/sponsor/

hkml's patch mails searching is only for interactive mode, and not very beautiful. For cleaner navigation and more tooling use case (e.g., extract searched patches as mbox files or parse the list output), I added the command line option supports[1] of the feature.

E.g., 'hkml list linux-mm --patches_for reviewer "SeongJae Park <sj@kernel.org>"' will list patch maisl touching files that I maintain.

[1] https://github.com/sjp38/hackermail/blob/master/USAGE.md#patches-filtering

#hkml

I'm honored to present DAMON at Kernel Recipes 2025. Looking forward to meeting you there!

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

Another podcast interview with me from a few weeks ago:
https://www.youtube.com/watch?v=DZzFG_zhFnY
that focuses a lot on the corporate interaction and involvement in open source projects.

Just pushed a new hkml feature for finding patch mails touching files for a reviewer based on MAINTAINERS file. More stabilizations and improvements would be needed, but seems working in a way? Kudos to @ljs for sharing the idea!

To use the feature, open mails list using 'hkml list' on linux tree, press 'm' key to open menu, and select 'search mails' item.

[1] https://github.com/sjp38/hackermail/blob/master/release_note

#hkml

Call for proposals of Linux Plumbers Conference (LPC) 2025 is now open!

The Linux Plumbers Conference is the premier event for developers working at all levels of the plumbing layer and beyond. Taking place on Thursday 11th, Friday 12th and Saturday 13th of December, this year we will be both in person and remote. The in-person venue is the Toranomon Hills Forum, Tokyo, Japan.

Please refer to our latest blog post for more details.

https://lpc.events/blog/current/index.php/2025/05/14/submission-time-for-linux-plumbers-2025/

I sometimes get confused at DAMON build configs. Maybe some distros enabling DAMON might gone or going through similar problems.

I hence just sent an RFC series for simplifying it by build-enabling DAMON by default.

https://lore.kernel.org/20250512182716.50245-1-sj@kernel.org

#linux #kernel #damon

Based on a feedback from my colleague, we implemented an hkml [1] feature for finding patch mails that need more or no more attentions based on 'Reviewed-by:' tags.

Open mails list using 'hkml list', press 'm' key to open menu, and select 'search mails' item.

[1] https://github.com/sjp38/hackermail

#hkml

Researchers found automatically tuning parameters can improve memory tieirng performance by 2x, using DAMON and SK hynix' DAMON-based memory tiering solution as a part of the research.

https://arxiv.org/pdf/2504.18714

#linux #kernel #damon

I'm sure @sj will be happy to hear that very soon the kernel in @opensuse Tumbleweed and later Leap 16.0 will be built with DAMON enabled!