linux-6.8/mm/Kconfig

1 # SPDX-License-Identifier: GPL-2.0-only
33 	  compress them into a dynamically allocated RAM-based memory pool.
62 	  swapped out again, it will be re-compressed.
79 	prompt "Default compressor"
94 	  command line 'zswap.compressor=' option.
210 	  zsmalloc is a slab-based memory allocator designed to store
225 	int "Maximum number of physical pages per-zspage"
227 	range 4 16
303 	  Try running: slabinfo -DA
340 	  utilization of a direct-mapped memory-side-cache. See section
343 	  the presence of a memory-side-cache. There are also incidental
353 	  after runtime detection of a direct-mapped memory-side-cache.
369 	  On non-ancient distros (post-2000 ones) N is usually a safe choice.
384 	  ELF-FDPIC binfmt's brk and stack allocator.
388 	  userspace.  Since that isn't generally a problem on no-MMU systems,
391 	  See Documentation/admin-guide/mm/nommu-mmap.rst for more information.
412 	  This option is best suited for non-NUMA systems with
428 	  memory hot-plug systems.  This is normal.
432 	  hot-plug and hot-remove.
502 # Keep arch NUMA mapping infrastructure post-init.
548 	  See Documentation/admin-guide/mm/memory-hotplug.rst for more information.
550 	  Say Y here if you want all hot-plugged memory blocks to appear in
552 	  Say N here if you want the default policy to keep all hot-plugged
571 # Heavily threaded applications may benefit from splitting the mm-wide
575 # ARM's adjust_pte (unused if VIPT) depends on mm-wide page_table_lock.
576 # PA-RISC 7xxx's spinlock_t would enlarge struct page from 32 to 44 bytes.
578 # a per-page lock leads to problems when multiple tables need to be locked
628 	  linux-mm@kvack.org.
674 	  Allows the pageblock_order value to be dynamic instead of just standard
685 	int "Maximum scale factor of PCP (Per-CPU pageset) batch allocate/free"
687 	range 0 6
689 	  In page allocator, PCP (Per-CPU pageset) is refilled and drained in
703 	  Enable bounce buffers for devices that cannot access the full range of
772 	  allocator for chunks in 2^N*PAGE_SIZE amounts - which is frequently
781 	  long-term mappings means that the space is wasted.
791 	  See Documentation/admin-guide/mm/nommu-mmap.rst for more information.
857 	bool "Read-only THP for filesystems (EXPERIMENTAL)"
861 	  Allow khugepaged to put read-only file-backed pages in THP.
896 	  subsystems to allocate big physically-contiguous blocks of memory.
944 	  soft-dirty bit on pte-s. This bit it set when someone writes
948 	  See Documentation/admin-guide/mm/soft-dirty.rst for more details.
954 	int "Default maximum user stack size for 32-bit processes (MB)"
956 	range 8 2048
959 	  This is the maximum stack size in Megabytes in the VM layout of 32-bit
998 	  See Documentation/admin-guide/mm/idle_page_tracking.rst for
1008 	  checking, an architecture-agnostic way to find the stack pointer
1040 	  "device-physical" addresses which is needed for using a DAX
1046 # Helpers to mirror range of the CPU page tables of a process into device page
1079 	  suitable for 64-bit architectures with CONFIG_FLATMEM or
1081 	  enough room for additional bits in page->flags.
1100 	bool "Enable infrastructure for get_user_pages()-related unit tests"
1104 	  to make ioctl calls that can launch kernel-based unit tests for
1109 	  the non-_fast variants.
1111 	  There is also a sub-test that allows running dump_page() on any
1113 	  range of user-space addresses. These pages are either pinned via
1212 	  file-backed memory types like shmem and hugetlbfs.
1215 # multi-gen LRU {
1217 	bool "Multi-Gen LRU"
1219 	# make sure folio->flags has enough spare bits
1223 	  Documentation/admin-guide/mm/multigen_lru.rst for details.
1229 	  This option enables the multi-gen LRU by default.
1238 	  This option has a per-memcg and per-node memory overhead.
1252 	  Allow per-vma locking during page fault handling.