Pull MM updates from Andrew Morton: - "selftests/mm: clean up build output and verbosity" (Li Wang) Remove some noise from the MM selftests build - "mm: Free contiguous order-0 pages efficiently" (Ryan Roberts) Speed up the freeing of a batch of 0-order pages by first scanning them for coalescing opportunities. This is applicable to vfree() and to the releasing of frozen pages - "mm/damon: introduce DAMOS failed region quota charge ratio" (SeongJae Park) Address a DAMOS usability issue: The DAMOS quota often exhausts prematurely because it charges for all memory attempted, causing slow and inconsistent performance when actions fail on unreclaimable memory. To fix this, a new feature lets users set a smaller, flexible quota charge ratio (via a numerator and denominator) for failed regions. Since failed actions cause less overhead, reducing their quota cost ensures more predictable and efficient DAMOS processing - "selftests/cgroup: improve zswap tests robustness and support large page sizes" (Li Wang) Fix various spurious failures and improves the overall robustness of the cgroup zswap selftests - "fix MAP_DROPPABLE not supported errno" (Anthony Yznaga) Fix an issue in the mlock selftests on arm32 - "mm: huge_memory: clean up defrag sysfs with shared" (Breno Leitao) Some maintenance work in the huge_memory code - "treewide: fixup gfp_t printks" (Brendan Jackman) Use the special vprintf() gfp_t conversion in various places - "mm: Fix vmemmap optimization accounting and initialization" (Muchun Song) Fix several bugs in the vmemmap optimization, mainly around incorrect page accounting and memmap initialization in the DAX and memory hotplug paths. It also fixes pageblock migratetype initialization and struct page initialization for ZONE_DEVICE compound pages - "mm/damon: repost non-hotfix reviewed patches in damon/next tree" A sprinkle of unrelated minor bugfixes for DAMON - "mm: remove page_mapped()" (David Hildenbrand) Remove this function from the tree, replacing it with folio_mapped() - "mm/damon: let DAMON be paused and resumed" (SeongJae Park) Allow DAMON to be paused and resumed without losing its current state - "kasan: hw_tags: Disable tagging for stack and page-tables" (Muhammad Usama Anjum) Simplify and speed up kasan by removing its ineffective tagging of stacks and page tables - "mm/damon/reclaim,lru_sort: monitor all system rams by default" (SeongJae Park) Simplify deployment on diverse hardware like NUMA systems by updating DAMON_RECLAIM and DAMON_LRU_SORT to automatically monitor the physical address range covering all System RAM areas by default, replacing the overly restrictive behavior that only targeted the single largest memory block to save on negligible overhead - "mm/damon/sysfs: document filters/ directory as deprecated" (SeongJae Park) Update some DAMON docs - "mm: use spinlock guards for zone lock" (Dmitry Ilvokhin) Switch zone->lock handling over to using the guard() mechanisms - "mm/filemap: tighten mmap_miss hit accounting" (fujunjie) Fix a flaw where the mmap_miss counter over-credited page cache hits during fault-arounds and page-fault retries. This results in significant reduction of redundant synchronous mmap readahead I/O, drastically cutting down execution time and gigabytes read for sparse random or strided memory access workloads - "selftests/cgroup: Fix false positive failures in test_percpu_basic" (Li Wang) Fix a couple of false-positives in the cgroup kmem selftests - "mm/damon/reclaim: support monitoring intervals auto-tuning" (SeongJae Park) Add a new parameter to DAMON permitting DAMON_RECLAIM to automatically tune DAMON's sampling and aggregation intervals - "mm/damon/stat: add kdamond_pid parameter" (SeongJae Park) Change DAMON_STAT to provide the pid of its kdamond - "mm/kmemleak: dedupe verbose scan output" (Breno Leitao) Remove large amounts of duplicated backtraces from the verbose-mode kmemleak output - "mm: remove CONFIG_HAVE_BOOTMEM_INFO_NODE (Part 1)" (David Hildenbrand) Reduce our use of CONFIG_HAVE_BOOTMEM_INFO_NODE, with a view to removing it entirely in a later series - "mm/damon: validate min_region_size to be power of 2" (Liew Rui Yan) Prevent users from passing a non-power-of-2 value of `addr_unit', as this later results in undesirable behavior - "mm: document read_pages and simplify usage" (Frederick Mayle) - "tools/mm/page-types: Fix misc bugs" (Ye Liu) Fix three issues in tools/mm/page-types.c - "mm: misc cleanups from __GFP_UNMAPPED series" (Brendan Jackman) Implement several cleanups in the page allocator and related code - "mm, swap: swap table phase IV: unify allocation" (Kairui Song) Unify the allocation and charging of anon and shmem swap in folios, provides better synchronization, consolidates the metadata management, hence dropping the static array and map, and improves performance - "mm/damon: introduce data attributes monitoring" (SeongJae Park( Extend DAMON to monitor general data attributes other than accesses - "mm/vmalloc: free unused pages on vrealloc() shrink" (Shivam Kalra) Implement the TODO in vrealloc() to unmap and free unused pages when shrinking across a page boundary - "mm/damon: documentation and comment fixes" (niecheng) - "remove mmap_action success, error hooks" (Lorenzo Stoakes) Eliminate custom hooks from mmap_action by removing the problematic success_hook which allowed drivers to improperly access uninitialized VMAs. It replaces the error_hook with a simple error-code field and updates the memory char driver accordingly - "mm/damon: minor improvements for code readability and tests" (SeongJae Park) - "mm/damon: fix macro arguments and clarify quota goals doc" (Maksym Shcherba) - "userfaultfd: merge fs/userfaultfd.c into mm/userfaultfd.c" (Mike Rapoport) - "mm/mglru: improve reclaim loop and dirty folio" (Kairui Song and others) Clean up and slightly improves MGLRU's reclaim loop and dirty writeback handling. Large performance improvements are measured - "use vma locks for proc/pid/{smaps|numa_maps} reads" (Suren Baghdasaryan) Use per-vma locks when reading /proc/pid/smaps and numa_maps similar to reduce contention on central mmap_lock - "refactors thpsize_shmem_enabled_store() and thpsize_shmem_enabled_show()" (Ran Xiaokai) Some cleanup work in the THP code - "selftests/memfd: fix compilation warnings" (Konstantin Khorenko) Fix a few build glitches in the memfd selftest code. - "memcg: shrink obj_stock_pcp and cache multiple objcgs" (Shakeel Butt) Resolve a 68% performance regression caused by NUMA-node cache thrashing around struct obj_stock_pcp by shrinking its existing fields and expanding it into a multi-slot array that caches up to five obj_cgroup pointers per CPU, allowing per-node variants of the same memcg to coexist within a single 64-byte cache line. - "zram: writeback fixes" (Sergey Senozhatsky) address a couple of unrelated zram writeback issues - "mm: switch THP shrinker to list_lru" (Johannes Weiner) Resolve NUMA-awareness issues and streamlines callsite interaction by refactoring and extending the list_lru API to completely replace the complex, open-coded deferred split queue for Transparent Huge Pages - "mm: improve large folio readahead for exec memory" (Usama Arif) Improve large-folio readahead on systems like 64K-page arm64 by preventing the mmap_miss check from permanently disabling target-oriented VM_EXEC readahead, and by generalizing the force_thp_readahead gate to support mappings with any usefully large maximum folio order under the cache cap. - "userfaultfd/pagemap: pre-existing fixes" (Kiryl Shutsemau) Fix a bunch of minor issues in the userfaultfd/pagemap, all of which were flagged by Sashiko review of proposed new material - "mm/sparse-vmemmap: Provide generic vmemmap_set_pmd() and vmemmap_check_pmd()" (Muchun Song) Provide generic versions of these two functions so the four arch-specific implementations can be removed. - "mm/swap, PM: hibernate: fix swapoff race in uswsusp by pinning swap device" (Youngjun Park) Address a uswsusp-vs-swapoff race and reduces the swap device reference taking/releasing frequency. - "mm/hmm: A fix and a selftest" (Dev Jain) * tag 'mm-stable-2026-06-18-09-26' of git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm: (321 commits) selftests/mm/hmm-tests: test pagemap reads of PMD device-private entries fs/proc/task_mmu: do not warn on seeing non-migration pmd entry lib/test_hmm: check alloc_page_vma() return value and handle OOM mm/compaction: cap compact_gap() at COMPACT_CLUSTER_MAX mm/swap: remove redundant swap device reference in alloc/free mm/swap, PM: hibernate: fix swapoff race in uswsusp by pinning swap device mm/filemap: use folio_next_index() for start vmalloc: fix NULL pointer dereference in is_vm_area_hugepages() sparc/mm: drop vmemmap_check_pmd helper and use generic code loongarch/mm: drop vmemmap_check_pmd helper and use generic code riscv/mm: drop vmemmap_pmd helpers and use generic code arm64/mm: drop vmemmap_pmd helpers and use generic code mm/sparse-vmemmap: provide generic vmemmap_set_pmd() and vmemmap_check_pmd() rust: page: mark Page::nid as inline userfaultfd: build __VMA_UFFD_FLAGS from config-gated masks userfaultfd: gate must_wait writability check on pte_present() mm/huge_memory: preserve pmd_swp_uffd_wp on device-private PMD downgrade fs/proc/task_mmu: fix hugetlb self-deadlock in pagemap_scan_pte_hole() fs/proc/task_mmu: use huge_page_size() in pagemap_scan_hugetlb_entry() fs/proc/task_mmu: fix make_uffd_wp_huge_pte() prot-update race ...
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| @@ -2067,6 +2067,10 @@ Kernel parameters · 2066 unmodified lines | ||
| 2067 | 2067 | Format: nn[KMGTPE] or (node format) |
| 2068 | 2068 | <node>:nn[KMGTPE][,<node>:nn[KMGTPE]] |
| 2069 | 2069 | |
| 2070 | + The size must be a multiple of the gigantic page size. | |
| 2071 | + When using node format, this applies to each per-node size. | |
| 2072 | + Missaligned values are dropped with a warning. | |
| 2073 | + | |
| 2070 | 2074 | Reserve a CMA area of given size and allocate gigantic |
| 2071 | 2075 | hugepages using the CMA allocator. If enabled, the |
| 2072 | 2076 | boot-time allocation of gigantic hugepages is skipped. |
| @@ -75,7 +75,7 @@ Make DAMON_LRU_SORT reads the input parameters again, except ``enabled``. · 74 unmodified lines | ||
| 75 | 75 | |
| 76 | 76 | Input parameters that updated while DAMON_LRU_SORT is running are not applied |
| 77 | 77 | by default. Once this parameter is set as ``Y``, DAMON_LRU_SORT reads values |
| 78 | −of parametrs except ``enabled`` again. Once the re-reading is done, this | |
| 78 | +of parameters except ``enabled`` again. Once the re-reading is done, this | |
| 79 | 79 | parameter is set as ``N``. If invalid parameters are found while the |
| 80 | 80 | re-reading, DAMON_LRU_SORT will be disabled. |
| 81 | 81 | |
| @@ -246,7 +246,8 @@ monitor_region_start · 164 unmodified lines | ||
| 246 | 246 | Start of target memory region in physical address. |
| 247 | 247 | |
| 248 | 248 | The start physical address of memory region that DAMON_LRU_SORT will do work |
| 249 | −against. By default, biggest System RAM is used as the region. | |
| 249 | +against. By default, the system's entire physical memory is used as the | |
| 250 | +region. | |
| 250 | 251 | |
| 251 | 252 | monitor_region_end |
| 252 | 253 | ------------------ |
| @@ -254,7 +255,8 @@ monitor_region_end · 1 unmodified line | ||
| 254 | 255 | End of target memory region in physical address. |
| 255 | 256 | |
| 256 | 257 | The end physical address of memory region that DAMON_LRU_SORT will do work |
| 257 | −against. By default, biggest System RAM is used as the region. | |
| 258 | +against. By default, the system's entire physical memory is used as the | |
| 259 | +region. | |
| 258 | 260 | |
| 259 | 261 | addr_unit |
| 260 | 262 | --------- |
| @@ -67,7 +67,7 @@ Make DAMON_RECLAIM reads the input parameters again, except ``enabled``. · 66 unmodified lines | ||
| 67 | 67 | |
| 68 | 68 | Input parameters that updated while DAMON_RECLAIM is running are not applied |
| 69 | 69 | by default. Once this parameter is set as ``Y``, DAMON_RECLAIM reads values |
| 70 | −of parametrs except ``enabled`` again. Once the re-reading is done, this | |
| 70 | +of parameters except ``enabled`` again. Once the re-reading is done, this | |
| 71 | 71 | parameter is set as ``N``. If invalid parameters are found while the |
| 72 | 72 | re-reading, DAMON_RECLAIM will be disabled. |
| 73 | 73 | |
| @@ -85,6 +85,17 @@ identifies the region as cold, and reclaims it. · 11 unmodified lines | ||
| 85 | 85 | |
| 86 | 86 | 120 seconds by default. |
| 87 | 87 | |
| 88 | +autotune_monitoring_intervals | |
| 89 | +----------------------------- | |
| 90 | + | |
| 91 | +If this parameter is set as ``Y``, DAMON_RECLAIM automatically tunes DAMON's | |
| 92 | +sampling and aggregation intervals. The auto-tuning aims to capture meaningful | |
| 93 | +amount of access events in each DAMON-snapshot, while keeping the sampling | |
| 94 | +interval 5 milliseconds in minimum, and 10 seconds in maximum. Setting this as | |
| 95 | +``N`` disables the auto-tuning. | |
| 96 | + | |
| 97 | +Disabled by default. | |
| 98 | + | |
| 88 | 99 | quota_ms |
| 89 | 100 | -------- |
| 90 | 101 | |
| @@ -229,7 +240,8 @@ Start of target memory region in physical address. · 138 unmodified lines | ||
| 229 | 240 | |
| 230 | 241 | The start physical address of memory region that DAMON_RECLAIM will do work |
| 231 | 242 | against. That is, DAMON_RECLAIM will find cold memory regions in this region |
| 232 | −and reclaims. By default, biggest System RAM is used as the region. | |
| 243 | +and reclaims. By default, the system's entire physical memory is used as the | |
| 244 | +region. | |
| 233 | 245 | |
| 234 | 246 | monitor_region_end |
| 235 | 247 | ------------------ |
| @@ -238,7 +250,8 @@ End of target memory region in physical address. · 2 unmodified lines | ||
| 238 | 250 | |
| 239 | 251 | The end physical address of memory region that DAMON_RECLAIM will do work |
| 240 | 252 | against. That is, DAMON_RECLAIM will find cold memory regions in this region |
| 241 | −and reclaims. By default, biggest System RAM is used as the region. | |
| 253 | +and reclaims. By default, the system's entire physical memory is used as the | |
| 254 | +region. | |
| 242 | 255 | |
| 243 | 256 | addr_unit |
| 244 | 257 | --------- |
| @@ -89,3 +89,10 @@ percentiles of the idle time values via this read-only parameter. Reading the · 88 unmodified lines | ||
| 89 | 89 | parameter returns 101 idle time values in milliseconds, separated by comma. |
| 90 | 90 | Each value represents 0-th, 1st, 2nd, 3rd, ..., 99th and 100th percentile idle |
| 91 | 91 | times. |
| 92 | + | |
| 93 | +kdamond_pid | |
| 94 | +----------- | |
| 95 | + | |
| 96 | +PID of the DAMON thread. | |
| 97 | + | |
| 98 | +If DAMON_STAT is enabled, this becomes the PID of the worker thread. Else, -1. | |
| @@ -66,11 +66,17 @@ comma (","). · 65 unmodified lines | ||
| 66 | 66 | │ :ref:`kdamonds <sysfs_kdamonds>`/nr_kdamonds |
| 67 | 67 | │ │ :ref:`0 <sysfs_kdamond>`/state,pid,refresh_ms |
| 68 | 68 | │ │ │ :ref:`contexts <sysfs_contexts>`/nr_contexts |
| 69 | − │ │ │ │ :ref:`0 <sysfs_context>`/avail_operations,operations,addr_unit | |
| 69 | + │ │ │ │ :ref:`0 <sysfs_context>`/avail_operations,operations,addr_unit, | |
| 70 | + │ │ │ │ pause | |
| 70 | 71 | │ │ │ │ │ :ref:`monitoring_attrs <sysfs_monitoring_attrs>`/ |
| 71 | 72 | │ │ │ │ │ │ intervals/sample_us,aggr_us,update_us |
| 72 | 73 | │ │ │ │ │ │ │ intervals_goal/access_bp,aggrs,min_sample_us,max_sample_us |
| 73 | 74 | │ │ │ │ │ │ nr_regions/min,max |
| 75 | + │ │ │ │ │ │ :ref:`probes <damon_usage_sysfs_probes>`/nr_probes | |
| 76 | + │ │ │ │ │ │ │ 0/filters/nr_filters | |
| 77 | + │ │ │ │ │ │ │ │ 0/type,matching,allow,path | |
| 78 | + │ │ │ │ │ │ │ │ ... | |
| 79 | + │ │ │ │ │ │ │ ... | |
| 74 | 80 | │ │ │ │ │ :ref:`targets <sysfs_targets>`/nr_targets |
| 75 | 81 | │ │ │ │ │ │ :ref:`0 <sysfs_target>`/pid_target,obsolete_target |
| 76 | 82 | │ │ │ │ │ │ │ :ref:`regions <sysfs_regions>`/nr_regions |
| @@ -83,18 +89,23 @@ comma (","). · 6 unmodified lines | ||
| 83 | 89 | │ │ │ │ │ │ │ │ sz/min,max |
| 84 | 90 | │ │ │ │ │ │ │ │ nr_accesses/min,max |
| 85 | 91 | │ │ │ │ │ │ │ │ age/min,max |
| 86 | − │ │ │ │ │ │ │ :ref:`quotas <sysfs_quotas>`/ms,bytes,reset_interval_ms,effective_bytes,goal_tuner | |
| 92 | + │ │ │ │ │ │ │ :ref:`quotas <sysfs_quotas>`/ms,bytes,reset_interval_ms, | |
| 93 | + │ │ │ │ │ │ │ effective_bytes,goal_tuner, | |
| 94 | + │ │ │ │ │ │ │ fail_charge_num,fail_charge_denom | |
| 87 | 95 | │ │ │ │ │ │ │ │ weights/sz_permil,nr_accesses_permil,age_permil |
| 88 | 96 | │ │ │ │ │ │ │ │ :ref:`goals <sysfs_schemes_quota_goals>`/nr_goals |
| 89 | 97 | │ │ │ │ │ │ │ │ │ 0/target_metric,target_value,current_value,nid,path |
| 90 | 98 | │ │ │ │ │ │ │ :ref:`watermarks <sysfs_watermarks>`/metric,interval_us,high,mid,low |
| 91 | 99 | │ │ │ │ │ │ │ :ref:`{core_,ops_,}filters <sysfs_filters>`/nr_filters |
| 92 | − │ │ │ │ │ │ │ │ 0/type,matching,allow,memcg_path,addr_start,addr_end,target_idx,min,max | |
| 100 | + │ │ │ │ │ │ │ │ 0/type,matching,allow,memcg_path,addr_start,addr_end,damon_target_idx,min,max | |
| 93 | 101 | │ │ │ │ │ │ │ :ref:`dests <damon_sysfs_dests>`/nr_dests |
| 94 | 102 | │ │ │ │ │ │ │ │ 0/id,weight |
| 95 | 103 | │ │ │ │ │ │ │ :ref:`stats <sysfs_schemes_stats>`/nr_tried,sz_tried,nr_applied,sz_applied,sz_ops_filter_passed,qt_exceeds,nr_snapshots,max_nr_snapshots |
| 96 | 104 | │ │ │ │ │ │ │ :ref:`tried_regions <sysfs_schemes_tried_regions>`/total_bytes |
| 97 | 105 | │ │ │ │ │ │ │ │ 0/start,end,nr_accesses,age,sz_filter_passed |
| 106 | + │ │ │ │ │ │ │ │ │ probes | |
| 107 | + │ │ │ │ │ │ │ │ │ │ 0/hits | |
| 108 | + │ │ │ │ │ │ │ │ │ │ ... | |
| 98 | 109 | │ │ │ │ │ │ │ │ ... |
| 99 | 110 | │ │ │ │ │ │ ... |
| 100 | 111 | │ │ │ │ ... |
| @@ -194,9 +205,9 @@ details). At the moment, only one context per kdamond is supported, so only · 93 unmodified lines | ||
| 194 | 205 | contexts/<N>/ |
| 195 | 206 | ------------- |
| 196 | 207 | |
| 197 | −In each context directory, three files (``avail_operations``, ``operations`` | |
| 198 | −and ``addr_unit``) and three directories (``monitoring_attrs``, ``targets``, | |
| 199 | −and ``schemes``) exist. | |
| 208 | +In each context directory, four files (``avail_operations``, ``operations``, | |
| 209 | +``addr_unit`` and ``pause``) and three directories (``monitoring_attrs``, | |
| 210 | +``targets``, and ``schemes``) exist. | |
| 200 | 211 | |
| 201 | 212 | DAMON supports multiple types of :ref:`monitoring operations |
| 202 | 213 | <damon_design_configurable_operations_set>`, including those for virtual address |
| @@ -214,6 +225,9 @@ reading from the ``operations`` file. · 11 unmodified lines | ||
| 214 | 225 | ``addr_unit`` file is for setting and getting the :ref:`address unit |
| 215 | 226 | <damon_design_addr_unit>` parameter of the operations set. |
| 216 | 227 | |
| 228 | +``pause`` file is for setting and getting the :ref:`pause request | |
| 229 | +<damon_design_execution_model_and_data_structures>` parameter of the context. | |
| 230 | + | |
| 217 | 231 | .. _sysfs_monitoring_attrs: |
| 218 | 232 | |
| 219 | 233 | contexts/<N>/monitoring_attrs/ |
| @@ -221,8 +235,8 @@ contexts/<N>/monitoring_attrs/ · 1 unmodified line | ||
| 221 | 235 | |
| 222 | 236 | Files for specifying attributes of the monitoring including required quality |
| 223 | 237 | and efficiency of the monitoring are in ``monitoring_attrs`` directory. |
| 224 | −Specifically, two directories, ``intervals`` and ``nr_regions`` exist in this | |
| 225 | −directory. | |
| 238 | +Specifically, three directories, ``intervals``, ``nr_regions`` and ``probes`` | |
| 239 | +exist in this directory. | |
| 226 | 240 | |
| 227 | 241 | Under ``intervals`` directory, three files for DAMON's sampling interval |
| 228 | 242 | (``sample_us``), aggregation interval (``aggr_us``), and update interval |
| @@ -256,6 +270,29 @@ tuning-applied current values of the two intervals can be read from the · 27 unmodified lines | ||
| 256 | 270 | ``sample_us`` and ``aggr_us`` files after writing ``update_tuned_intervals`` to |
| 257 | 271 | the ``state`` file. |
| 258 | 272 | |
| 273 | +.. _damon_usage_sysfs_probes: | |
| 274 | + | |
| 275 | +contexts/<N>/monitoring_attrs/probes/ | |
| 276 | +------------------------------------- | |
| 277 | + | |
| 278 | +A directory for registering :ref:`data attributes monitoring | |
| 279 | +<damon_design_data_attrs_monitoring>` probes. | |
| 280 | + | |
| 281 | +In the beginning, this directory has only one file, ``nr_probes``. Writing a | |
| 282 | +number (``N``) to the file creates the number of child directories named ``0`` | |
| 283 | +to ``N-1``. Each directory represents each monitoring probe. | |
| 284 | + | |
| 285 | +In each probe directory, one directory, ``filters`` exists. The directory | |
| 286 | +contains files for installing filters for the probe, that is used to determine | |
| 287 | +the data attribute for the probe. | |
| 288 | + | |
| 289 | +In the beginning, ``filters`` directory has only one file, ``nr_filters``. | |
| 290 | +Writing a number (``N``) to the file creates the number of child directories | |
| 291 | +named ``0`` to ``N-1``. Each directory represents each filter and works in a | |
| 292 | +way similar to that for :ref:`DAMOS filter <sysfs_filters>`. When the filter | |
| 293 | +``type`` is ``memcg``, ``path`` file acts as ``memcg_path`` for :ref:`DAMOS | |
| 294 | +filter <sysfs_filters>`. | |
| 295 | + | |
| 259 | 296 | .. _sysfs_targets: |
| 260 | 297 | |
| 261 | 298 | contexts/<N>/targets/ |
| @@ -337,7 +374,7 @@ to ``N-1``. Each directory represents each DAMON-based operation scheme. · 75 unmodified lines | ||
| 337 | 374 | schemes/<N>/ |
| 338 | 375 | ------------ |
| 339 | 376 | |
| 340 | −In each scheme directory, eight directories (``access_pattern``, ``quotas``, | |
| 377 | +In each scheme directory, nine directories (``access_pattern``, ``quotas``, | |
| 341 | 378 | ``watermarks``, ``core_filters``, ``ops_filters``, ``filters``, ``dests``, |
| 342 | 379 | ``stats``, and ``tried_regions``) and three files (``action``, ``target_nid`` |
| 343 | 380 | and ``apply_interval``) exist. |
| @@ -377,9 +414,10 @@ schemes/<N>/quotas/ · 33 unmodified lines | ||
| 377 | 414 | The directory for the :ref:`quotas <damon_design_damos_quotas>` of the given |
| 378 | 415 | DAMON-based operation scheme. |
| 379 | 416 | |
| 380 | −Under ``quotas`` directory, five files (``ms``, ``bytes``, | |
| 381 | −``reset_interval_ms``, ``effective_bytes`` and ``goal_tuner``) and two | |
| 382 | −directories (``weights`` and ``goals``) exist. | |
| 417 | +Under ``quotas`` directory, seven files (``ms``, ``bytes``, | |
| 418 | +``reset_interval_ms``, ``effective_bytes``, ``goal_tuner``, ``fail_charge_num`` | |
| 419 | +and ``fail_charge_denom``) and two directories (``weights`` and ``goals``) | |
| 420 | +exist. | |
| 383 | 421 | |
| 384 | 422 | You can set the ``time quota`` in milliseconds, ``size quota`` in bytes, and |
| 385 | 423 | ``reset interval`` in milliseconds by writing the values to the three files, |
| @@ -398,6 +436,13 @@ the background design of the feature and the name of the selectable algorithms. · 12 unmodified lines | ||
| 398 | 436 | Refer to :ref:`goals directory <sysfs_schemes_quota_goals>` for the goals |
| 399 | 437 | setup. |
| 400 | 438 | |
| 439 | +You can set the action-failed memory quota charging ratio by writing the | |
| 440 | +numerator and the denominator for the ratio to ``fail_charge_num`` and | |
| 441 | +``fail_charge_denom`` files, respectively. Reading those files will return the | |
| 442 | +current set values. Refer to :ref:`design | |
| 443 | +<damon_design_damos_quotas_failed_memory_charging_ratio>` for more details of | |
| 444 | +the ratio feature. | |
| 445 | + | |
| 401 | 446 | The time quota is internally transformed to a size quota. Between the |
| 402 | 447 | transformed size quota and user-specified size quota, smaller one is applied. |
| 403 | 448 | Based on the user-specified :ref:`goal <sysfs_schemes_quota_goals>`, the |
| @@ -429,10 +474,12 @@ to ``N-1``. Each directory represents each goal and current achievement. · 25 unmodified lines | ||
| 429 | 474 | Among the multiple feedback, the best one is used. |
| 430 | 475 | |
| 431 | 476 | Each goal directory contains five files, namely ``target_metric``, |
| 432 | −``target_value``, ``current_value`` ``nid`` and ``path``. Users can set and | |
| 477 | +``target_value``, ``current_value``, ``nid``, and ``path``. Users can set and | |
| 433 | 478 | get the five parameters for the quota auto-tuning goals that specified on the |
| 434 | 479 | :ref:`design doc <damon_design_damos_quotas_auto_tuning>` by writing to and |
| 435 | −reading from each of the files. Note that users should further write | |
| 480 | +reading from each of the files. Because the kernel does not update | |
| 481 | +``current_value``, reading it only makes sense when ``target_metric`` is | |
| 482 | +``user_input``. Note that users should further write | |
| 436 | 483 | ``commit_schemes_quota_goals`` to the ``state`` file of the :ref:`kdamond |
| 437 | 484 | directory <sysfs_kdamond>` to pass the feedback to DAMON. |
| 438 | 485 | |
| @@ -447,7 +494,7 @@ given DAMON-based operation scheme. · 8 unmodified lines | ||
| 447 | 494 | Under the watermarks directory, five files (``metric``, ``interval_us``, |
| 448 | 495 | ``high``, ``mid``, and ``low``) for setting the metric, the time interval |
| 449 | 496 | between check of the metric, and the three watermarks exist. You can set and |
| 450 | −get the five values by writing to the files, respectively. | |
| 497 | +get the five values by writing to and reading from the files, respectively. | |
| 451 | 498 | |
| 452 | 499 | Keywords and meanings of those that can be written to the ``metric`` file are |
| 453 | 500 | as below. |
| @@ -455,7 +502,7 @@ as below. · 1 unmodified line | ||
| 455 | 502 | - none: Ignore the watermarks |
| 456 | 503 | - free_mem_rate: System's free memory rate (per thousand) |
| 457 | 504 | |
| 458 | −The ``interval`` should written in microseconds unit. | |
| 505 | +The ``interval_us`` should be written in microseconds unit. | |
| 459 | 506 | |
| 460 | 507 | .. _sysfs_filters: |
| 461 | 508 | |
| @@ -471,10 +518,10 @@ directory can be used for installing filters regardless of their handled · 9 unmodified lines | ||
| 471 | 518 | layers. Filters that requested by ``core_filters`` and ``ops_filters`` will be |
| 472 | 519 | installed before those of ``filters``. All three directories have same files. |
| 473 | 520 | |
| 474 | −Use of ``filters`` directory can make expecting evaluation orders of given | |
| 475 | −filters with the files under directory bit confusing. Users are hence | |
| 476 | −recommended to use ``core_filters`` and ``ops_filters`` directories. The | |
| 477 | −``filters`` directory could be deprecated in future. | |
| 521 | +Use of ``filters`` directory can make filters evaluation orders confusing to | |
| 522 | +expect. For this reason, ``filters`` directory is deprecated. It is still | |
| 523 | +functioning, but is scheduled for removal in the near future. Users should use | |
| 524 | +``core_filters`` and ``ops_filters`` directories instead. | |
| 478 | 525 | |
| 479 | 526 | In the beginning, the directory has only one file, ``nr_filters``. Writing a |
| 480 | 527 | number (``N``) to the file creates the number of child directories named ``0`` |
| @@ -483,9 +530,9 @@ in the numeric order. · 2 unmodified lines | ||
| 483 | 530 | |
| 484 | 531 | Each filter directory contains nine files, namely ``type``, ``matching``, |
| 485 | 532 | ``allow``, ``memcg_path``, ``addr_start``, ``addr_end``, ``min``, ``max`` |
| 486 | −and ``target_idx``. To ``type`` file, you can write the type of the filter. | |
| 487 | −Refer to :ref:`the design doc <damon_design_damos_filters>` for available type | |
| 488 | −names, their meaning and on what layer those are handled. | |
| 533 | +and ``damon_target_idx``. To ``type`` file, you can write the type of the | |
| 534 | +filter. Refer to :ref:`the design doc <damon_design_damos_filters>` for | |
| 535 | +available type names, their meaning and on what layer those are handled. | |
| 489 | 536 | |
| 490 | 537 | For ``memcg`` type, you can specify the memory cgroup of the interest by |
| 491 | 538 | writing the path of the memory cgroup from the cgroups mount point to |
| @@ -495,7 +542,7 @@ files, respectively. For ``hugepage_size`` type, you can specify the minimum · 3 unmodified lines | ||
| 495 | 542 | and maximum size of the range (closed interval) to ``min`` and ``max`` files, |
| 496 | 543 | respectively. For ``target`` type, you can specify the index of the target |
| 497 | 544 | between the list of the DAMON context's monitoring targets list to |
| 498 | −``target_idx`` file. | |
| 545 | +``damon_target_idx`` file. | |
| 499 | 546 | |
| 500 | 547 | You can write ``Y`` or ``N`` to ``matching`` file to specify whether the filter |
| 501 | 548 | is for memory that matches the ``type``. You can write ``Y`` or ``N`` to |
| @@ -601,10 +648,19 @@ tried_regions/<N>/ · 99 unmodified lines | ||
| 601 | 648 | ------------------ |
| 602 | 649 | |
| 603 | 650 | In each region directory, you will find five files (``start``, ``end``, |
| 604 | −``nr_accesses``, ``age``, and ``sz_filter_passed``). Reading the files will | |
| 651 | +``nr_accesses``, ``age`` and ``sz_filter_passed``). Reading the files will | |
| 605 | 652 | show the properties of the region that corresponding DAMON-based operation |
| 606 | 653 | scheme ``action`` has tried to be applied. |
| 607 | 654 | |
| 655 | +tried_regions/<N>/probes/ | |
| 656 | +------------------------- | |
| 657 | + | |
| 658 | +In each region directory, one directory (``probes``) also exists. In the | |
| 659 | +directory, subdirectories named ``0`` to ``N-1`` exists. ``N`` is the number | |
| 660 | +of installed probes. In each number-named directory, a file (``hits``) exist. | |
| 661 | +Reading the file shows the number of data attributes monitoring probe-hit | |
| 662 | +positive samples of the region. | |
| 663 | + | |
| 608 | 664 | Example |
| 609 | 665 | ~~~~~~~ |
| 610 | 666 | |
| @@ -677,7 +733,7 @@ show results using tracepoint supporting tools like ``perf``. For example:: · 66 unmodified lines | ||
| 677 | 733 | |
| 678 | 734 | Each line of the perf script output represents each monitoring region. The |
| 679 | 735 | first five fields are as usual other tracepoint outputs. The sixth field |
| 680 | −(``target_id=X``) shows the ide of the monitoring target of the region. The | |
| 736 | +(``target_id=X``) shows the id of the monitoring target of the region. The | |
| 681 | 737 | seventh field (``nr_regions=X``) shows the total number of monitoring regions |
| 682 | 738 | for the target. The eighth field (``X-Y:``) shows the start (``X``) and end |
| 683 | 739 | (``Y``) addresses of the region in bytes. The ninth field (``X``) shows the |
| @@ -57,7 +57,7 @@ prominent because the size of each page isn't as huge as the PMD-sized · 56 unmodified lines | ||
| 57 | 57 | variant and there is less memory to clear in each page fault. Some |
| 58 | 58 | architectures also employ TLB compression mechanisms to squeeze more |
| 59 | 59 | entries in when a set of PTEs are virtually and physically contiguous |
| 60 | −and approporiately aligned. In this case, TLB misses will occur less | |
| 60 | +and appropriately aligned. In this case, TLB misses will occur less | |
| 61 | 61 | often. |
| 62 | 62 | |
| 63 | 63 | THP can be enabled system wide or restricted to certain tasks or even |
| @@ -210,7 +210,7 @@ PMD-mappable transparent hugepage:: · 146 unmodified lines | ||
| 210 | 210 | cat /sys/kernel/mm/transparent_hugepage/hpage_pmd_size |
| 211 | 211 | |
| 212 | 212 | All THPs at fault and collapse time will be added to _deferred_list, |
| 213 | −and will therefore be split under memory presure if they are considered | |
| 213 | +and will therefore be split under memory pressure if they are considered | |
| 214 | 214 | "underused". A THP is underused if the number of zero-filled pages in |
| 215 | 215 | the THP is above max_ptes_none (see below). It is possible to disable |
| 216 | 216 | this behaviour by writing 0 to shrink_underused, and enable it by writing |
| @@ -1034,6 +1034,8 @@ min(3% of current process size, user_reserve_kbytes) of free memory. · 1033 unmodified lines | ||
| 1034 | 1034 | This is intended to prevent a user from starting a single memory hogging |
| 1035 | 1035 | process, such that they cannot recover (kill the hog). |
| 1036 | 1036 | |
| 1037 | +This setting has no effect when overcommit_memory is set to 0 or 1. | |
| 1038 | + | |
| 1037 | 1039 | user_reserve_kbytes defaults to min(3% of the current process size, 128MB). |
| 1038 | 1040 | |
| 1039 | 1041 | If this is reduced to zero, then the user will be allowed to allocate |