Lines Matching +full:boot +full:- +full:pages
20 - The physical memory available to a machine can be adjusted at runtime, up- or
25 - Replacing hardware, such as DIMMs or whole NUMA nodes, without downtime. One
28 - Reducing energy consumption either by physically unplugging memory modules or
32 used to expose persistent memory, other performance-differentiated memory and
39 ------------------------------
54 ------------------------
71 --------------------------
80 relevant free pages from the page allocator After this phase, the memory is no
94 ------------------
112 --------------
152 -------------------------------
154 If auto-onlining of memory blocks isn't enabled, user-space has to manually
183 ------------------------------------
185 The kernel can be configured to try auto-onlining of newly added memory blocks.
189 The configured auto-online behavior can be observed via::
193 Auto-onlining can be enabled by writing ``online``, ``online_kernel`` or
201 Modifying the auto-online behavior will only affect all subsequently added
206 In corner cases, auto-onlining can fail. The kernel won't retry. Note that
207 auto-onlining is not expected to fail in default configurations.
215 -----------------------
218 movable pages off the affected memory block. As most kernel allocations, such as
248 ------------------------------------
250 The state (online/offline/going-offline) of a memory block can be observed
270 ------------------------------------------
279 ``auto_online_blocks`` read-write: set or get the default state of new memory
280 blocks; configure auto-onlining.
287 ``block_size_bytes`` read-only: the size in bytes of a memory block.
288 ``probe`` write-only: add (probe) selected memory blocks manually
293 ``uevent`` read-write: generic udev file for device subsystems.
294 ``crash_hotplug`` read-only: when changes to the system memory map
309 to trigger hwpoisoning of pages, for example, for testing purposes. Note that
314 ------------------------------------
339 ``online`` read-write: simplified interface to trigger onlining /
342 ``phys_device`` read-only: legacy interface only ever used on s390x to
344 ``phys_index`` read-only: the memory block id (XXX).
345 ``removable`` read-only: legacy interface that indicated whether a memory
349 ``state`` read-write: advanced interface to trigger onlining /
360 When reading, ``online``, ``offline`` and ``going-offline``
362 ``uevent`` read-write: generic uevent file for devices.
363 ``valid_zones`` read-only: when a block is online, shows the zone it
390 /sys/devices/system/node/node0/memory9 -> ../../memory/memory9
394 /sys/devices/system/memory/memory9/node0 -> ../../node/node0
397 -----------------------
403 ``memhp_default_state`` configure auto-onlining by essentially setting
406 using the ``contig-zones`` online policy. When
412 See Documentation/admin-guide/kernel-parameters.txt for a more generic
416 ------------------
432 ``memmap_on_memory`` read-write: Allocate memory for the memmap from
442 memory in a way that huge pages in bigger
457 ``online_policy`` read-write: Set the basic policy used for
460 ``contig-zones`` has been the kernel default
466 When set to ``contig-zones``, the kernel will
474 When set to ``auto-movable``, the kernel will
488 firmware-provided memory map early during boot
490 added and onlined later during boot (such as
491 done by virtio-mem or by some hypervisors
497 belonging to a virtio-mem device will be
499 special-casing units of memory blocks that can
505 ``auto_movable_ratio`` read-write: Set the maximum MOVABLE:KERNEL
506 memory ratio in % for the ``auto-movable``
512 All accounting is based on present memory pages
522 additional 1% deals with some pages being not
533 hotplugged by a virtio-mem device that got
536 virtio-mem device.
537 ``auto_movable_numa_aware`` read-write: Configure whether the
538 ``auto_movable_ratio`` in the ``auto-movable``
557 kernel zones can increase the number of possible transparent huge pages and
558 dynamically allocated huge pages.
564 Most user space pages, such as anonymous memory, and page cache pages are
572 ---------------
583 long-term pinning of pages, might not be able to deal with ZONE_MOVABLE at all.
592 ----------------------------------
596 the normal case, ZONE_MOVABLE can be used when allocating such pages just fine.
600 ZONE_MOVABLE, especially when fine-tuning zone ratios:
602 - Having a lot of offline memory blocks. Even offline memory blocks consume
606 - Memory ballooning without balloon compaction is incompatible with
607 ZONE_MOVABLE. Only some implementations, such as virtio-balloon and
615 - Gigantic pages are unmovable, resulting in user space consuming a
618 - Huge pages are unmovable when an architectures does not support huge
619 page migration, resulting in a similar issue as with gigantic pages.
621 - Page tables are unmovable. Excessive swapping, mapping extremely large
627 - In certain DAX configurations the memory map for the device memory will be
630 - KASAN can have a significant memory overhead, for example, consuming 1/8th of
633 - Long-term pinning of pages. Techniques that rely on long-term pinnings
635 ZONE_MOVABLE, and therefore, memory offlining. Pinned pages cannot reside
636 on ZONE_MOVABLE as that would turn these pages unmovable. Therefore, they
643 By default, all the memory configured at boot time is managed by the kernel
646 To enable ZONE_MOVABLE to include the memory present at boot and to control the
649 Documentation/admin-guide/kernel-parameters.rst for their description.
652 ---------------------------------
657 - Memory blocks with memory holes; this applies to memory blocks present during
658 boot and can apply to memory blocks hotplugged via the XEN balloon and the
659 Hyper-V balloon.
661 - Mixed NUMA nodes and mixed zones within a single memory block prevent memory
662 offlining; this applies to memory blocks present during boot only.
664 - Special memory blocks prevented by the system from getting offlined. Examples
665 include any memory available during boot on arm64 or memory blocks spanning
667 during boot only.
669 - Memory blocks overlapping with CMA areas cannot be offlined, this applies to
670 memory blocks present during boot only.
672 - Concurrent activity that operates on the same physical memory area, such as
673 allocating gigantic pages, can result in temporary offlining failures.
675 - Out of memory when dissolving huge pages, especially when HugeTLB Vmemmap
679 to dissolve the source huge page because it fails allocating (unmovable) pages
688 Further, when running into out of memory situations while migrating pages, or
689 when still encountering permanently unmovable pages within ZONE_MOVABLE
690 (-> BUG), memory offlining will keep retrying until it eventually succeeds.