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A number of DAMON changes for Linux 6.19-rc1 has merged into the mainline as a part of MM pull reqeust for Linux 6.19-rc1, which was sent by Andrew Morton. To list the changes here again: mm/damon: allow DAMOS auto-tuned for per-memcg per-node memory usage (patches) mm/damon: fixes for address alignment issues in DAMON_LRU_SORT and DAMON_RECLAIM (patches) mm/damon: misc documentation fixups (patches) mm/damon: support pin-point targets removal (patches) mm/damon/tests: fix memory bugs in kunit tests (patches) mm/damon/tests: add more tests for online parameters commit (patches) mm/damon: misc cleanups (patches)

Below is also sent as a mail to DAMON mailing list and relevant people. I’m working [1] on extending DAMON to monitor accesses that are made by specific CPUs, and/or for writes. The aimed usages include NUMA hit/miss monitoring [2], Kernel Same page Merging scan target selection [3,4], cache aware CPU scheduling, live migration target VM selection [5], and general NUMA-aware pages migration [6]. I posted its first working version as RFC v2 [7] about four months ago....

This post lists research papers and news articles citing DAMON. The list is best effort collection of the papers and articles, so may not be perfect. Taehyung Lee, Sumit Monga, Young Ik Eom, and Changwoo Min. 2025. Harnessing Page Access Frequency Distribution for Efficient Memory Tiering. ACM Trans. Comput. Syst. Just Accepted (November 2025). https://doi.org/10.1145/3777549 Introduces DAMON as a recently introduced way for doing page table based access tracking that mitigates the mointoring overhead....

From the very early days of DAMON, there were attempts to extend it for cpus-aware monitoring and write-only monitoring. In 2022, Xin Hao proposed extending DAMON for NUMA access statistics. In 2022 and 2025, Pedro Demarchi Gomes proposed extending DAMON for writes-only monitoring. Those proposals are not yet upstreamed though. We continued similar DAMON extension discussions publicly and privately, with multiple parties, though. I was recently taking some time on these, and happy to announce the first working prototype for the extensions....

TL; DR: damo report heatmap has recently advanced to support modern DAMON features including age tracking, snapshots, page level monitoring, and monitoring intervals auto-tuning. It will help users intuitively understand the monitored access patterns at a glance. DAMON in The Past: Full Recording based Monitoring At the beginning, DAMON was providing only the access frequency of each memory region in real time. Hence heatmap visualization, which shows the access frequency of each memory area in the timeline was the first and one of the best ways to see the access pattern....

TL; DR: try --draw_range all option of damo report heatmap if it shows not what you expected. --interactive_edit option can also be helpful, like below. Problem: Scoping of Huge Time/Space damo report heatmap outputs sometimes show no expected access pattern. It is sometimes just entirely black, or shows some access pattern but not what the user expected. This post is for explaining the reason and how you can work around....

We’re working on making DAMON to be used for page level properties based access monitoring. The idea is to let users describe specific page level properties that are interested in, and provides the size of the type of memory in each regions that DAMON found unique access pattern. Hence, users can know how much of memory of specific access temperature is having the type. For example, you can know how much of memory that not accessed for more than 20 minutes are having how much file-backed pages of a cgroup....