| TODOs |
| ===== |
| |
| WIP |
| --- |
| |
| merged in mm |
| - Handle non-power-of-two min_nr_regions aligning. |
| - ALIGN() is only for power of two alignment. |
| - merged in mm.git |
| - per-filtered-address-ragne prioritization |
| - do the temperature-prioritization for address filter-passed regions, |
| separately |
| - merged in mm.git |
| - respect min_nr_regions from beginning |
| - merged in mm.git |
| - fix sampling intervals overflow |
| - add CONFIG_DAMON_HARDENED for integrity checking |
| - allow stop-after-achieving DAMOS goal |
| - add per-goal quota tuning strategy |
| - consist: the current one, default. |
| - temporal: the new one. |
| - bpf: for future? |
| - fix walk_system_ram() type violation |
| - https://lore.kernel.org/20260129161029.48991-1-sj@kernel.org |
| |
| - mark DAMOS filters/ dir deprecated on doc |
| - cover all physical address space from DAMON modules |
| - add kdamond_pid to damon_stat. |
| - let DAMON_RECLAIM auto-tune intervals. |
| - kdamond pause/resume. |
| - Use it for drgn tests. |
| - Let DAMOS action failed region be charged in a different rate |
| - e.g., charge only 1 byte for 1 MiB of failed region. |
| |
| - Documentation cleanup: Make link from design to API |
| - deprecate sysfs filters/ in favor of {core,ops}_filters/ |
| - warn on use of filters/, by 2027 |
| - rename filters/ to filters_DEPRECATED/, by 2028 |
| - remove filters/ code and documentation, by 2029 |
| |
| Planning / Considering |
| ---------------------- |
| |
| - Aware 1 GiB hugetlb pages when auto-tuning intervals. |
| - Subtract 1 GiB hugetlb pages from the total size of memory. |
| - Let DAMON_STAT and DAMON_RECLAIM run in parallel. |
| - Let DAMON API callers share a kdamond |
| - What kdamond to share? |
| - A single one that always running, say, kdamond*<N>? |
| - Just the kdamond of the first caller that started (could be any |
| kdamond<N>? |
| - counters of interests |
| - for production level lightweight page-level monitoring |
| - let users register counters of interests |
| - when doing access check, check if the sample page is of the interest, |
| increase the counter. |
| - users know how many of each region is of the type, proportionally. |
| - nr_accesses will be the default counter |
| - add drgn selftests for DAMON modules. |
| - Support tlb flushing |
| - https://lore.kernel.org/all/a2fb10bd-b44a-350e-f693-82ecfa6f54a8@huawei.com/ |
| - automatic paddr regions detection |
| (handle hot(un)plugged memory regions) |
| - similar to vaddr, detect and cover all online memory as much as possible, |
| with a few holes. |
| - make DAMON_STAT cover multiple hot-[un]pluggable NUMA nodes |
| - implement and use kind of three big regions detection mechanism |
| - distinction of uncheckable memory |
| - not just say it is not accessed, but disclose the fact that it was unable |
| to check the access to, and apply merge-split with the fact. |
| - add kunit test for all parameters commit functions |
| - add damos_stat for auto-tuned zero size applying |
| |
| - DAMOS_KILL: DAMON-based OOM killing |
| - If DAMON_RECLAIM doesn't increase free memory, killing processes of hot |
| pages. |
| - implement pause/resume of kdamonds |
| - Or, let user feed nr_accesses and age of regions |
| - User can snapshot the last monitoring results and continue monitoring |
| from the status. |
| |
| - support (multiple) kdamosd |
| - per-noe memory bandwidth utilization DAMOS quota goal metric |
| - clarify possible monitoring results loss on usage doc. |
| - implement addr_unit commit kunit test |
| - implement addr_unit to/from core address conversion kunit test |
| - handle charged_ns overflow on 32bit machines |
| - cleanup damon_set_attrs() documentation |
| - add kunit test for damon_call() and damos_walk() |
| - DAMON-based khugepaged |
| - Make khugepaged listen DAMON's voice when collapsing |
| - Support multi contexts per kdamond |
| - Add sharable kdamond |
| - Run with auto-tuned intervals |
| - Let API callers report access information, read monitoring results and |
| add/remove DAMOS schemes |
| - Major callers would be DAMON modules |
| - damon_get_handle(), damon_report_access(), damos_add_folios() |
| - Let ABI users read monitoring results and DAMOS stat |
| - /sys/kernel/mm/damon/???/ |
| - DAMON_NUMA_MIGRATE |
| - Aim for not only traditional NUMA but also tiering |
| - Just extend mtier to every node, but CPU-aware. |
| - sysfs command for updating params (for restoring old params) |
| - write a selftest for sz_filter_passed |
| - contigurized-vddr |
| - trat end of a discrete region as start of next region |
| - connect regions before and after huge unmapped area |
| - connect regions of different virtual addresses |
| - Write API documentation |
| - no just kerenl doc, but more structured document is needed |
| - Let users decide regions split factor |
| - https://lore.kernel.org/20241026215311.148363-1-sj@kernel.org |
| - Let users periodically split regions without per-region subregions limit |
| - https://lore.kernel.org/20241026215311.148363-1-sj@kernel.org |
| - Sampling based page level properties based monitoring |
| - For DAMOS_STAT, do sampling for sz_filter_passed calculation |
| - Let user sets the number of samples per region for this |
| - Support reserved uninstall of DAMOS |
| - Allow running DAMOS scheme for only specific apply intervals |
| - Extend for memory bandwidth monitoring |
| - Extend for AMD IBS-based monitoring |
| - Extend for cache-set space monitoring |
| - Extend for cache-line space monitoring |
| - Require sub-page level monitoring (IBS?) |
| - Access/Contiguity-aware Memory Auto-scaling |
| - https://lore.kernel.org/damon/20240512193657.79298-1-sj@kernel.org |
| - Support cleaning sysfs input files up to committed values |
| - holistic heterogenous memory management |
| - address CPU-numa, CXL-numa, and device(e.g., GPU)-numa nodes |
| - DAMON_LRU_SORT auto-tuning |
| - Let auto-tuning using active/inactive memory ratio |
| - Selftests: Test DAMON online tuning |
| - Selftests: Test DAMOS online tuning |
| - Selftests: Test DAMOS filter |
| - Make 'age' counted by sample_interval rather than aggregation interval |
| - CPU time quota for DAMON monitirng |
| - monitoring part CPU usage statistics |
| - Setting resolution of damos tried_regions |
| - Should be able to control the directories population overhead when the |
| number of regions is big |
| - More DAMON modules |
| - DAMON-based THP hinting module |
| - rename nr_accesses/moving_accesses_bp |
| - mark nr_accesses as private |
| - use a dedicated struct for access rate |
| - let kdamond name be user-defined |
| - let DAMON modules share one kdamond |
| - unify DAMON modules |
| - support multiple contexts per kdamond |
| - DAMON-based VMA split/merge |
| - Help big VMA contention issue? |
| - We can further expose the monitoring results via vma name |
| - Reading results becomes very easy |
| - Contig memory access util monitoring |
| - WSS/RSS based processes sorting |
| - LRU-based monitoring ops |
| - Fixed granularity idleness monitoring |
| - Must be useful for further DAMON overhead/accuracy evaluation |
| - Improve regions-based monitoring quality |
| - Support cgroups |
| - Add __counted_by() annotation when ready |
| (https://lore.kernel.org/r/CAKwvOdkvGTGiWzqEFq=kzqvxSYP5vUj3g9Z-=MZSQROzzSa_dg@mail.gmail.com) |
| - Ideas from LSFMM |
| - Add operations driven access check |
| - Let it calls DAMON functions for noticed access and then let DAMON records |
| the access |
| - Take care of fairness on ACMA (e.g., NUMA) |
| - Consider hugetlb handling optimization |
| - DAMON_RECLAIM will meaninglessly try reclaiming hugetlb pages, consume |
| CPUs. Find a way to optimize. |
| - DAMON in process context |
| - Do the monitoring for each process in task_work context, like NUMA |
| balancing installs prot_none. |
| |
| Frozen |
| ------ |
| |
| Recently Done |
| ------------- |
| |
| - DAMOS stat/control improvement |
| - Show how many snapshots the scheme has processed |
| - Let DAMOS deactivated based on the number of processed snapshots |
| - Provide a tracepoint for DAMOS stat |
| - merged into 7.0-rc1 |
| - DAMON_LRU_SORT modernization |
| - merged into 7.0-rc1 |
| - hide kdamond and kdamond_lock from API callers |
| - merged into 7.0-rc1 |
| - modernize wss_estimation kselftest |
| - merged into 7.0-rc1 |
| - document modules usage on usage doc |
| - merged into 7.0-rc1 |
| |
| |
| Non-DAMON issues |
| ---------------- |
