Lines Matching full:page
9 the Linux kernel. This support is built on top of multiple page size support
11 support 4K and 2M (1G if architecturally supported) page sizes, ia64
12 architecture supports multiple page sizes 4K, 8K, 64K, 256K, 1M, 4M, 16M,
19 Users can use the huge page support in Linux kernel by either using the mmap
28 persistent hugetlb pages in the kernel's huge page pool. It also displays
29 default huge page size and information about the number of free, reserved
31 The huge page size is needed for generating the proper alignment and
32 size of the arguments to system calls that map huge page regions.
55 huge page from the pool of huge pages at fault time.
62 with each hugetlb page is enabled, the number of surplus huge pages
80 pages in the kernel's huge page pool. "Persistent" huge pages will be
81 returned to the huge page pool when freed by a task. A user with root
86 hugetlb page is enabled, we can fail to free the huge pages triggered by
93 Once a number of huge pages have been pre-allocated to the kernel huge page
103 Some platforms support multiple huge page sizes. To allocate huge pages
105 with a huge page size selection parameter "hugepagesz=<size>". <size> must
107 page size may be selected with the "default_hugepagesz=<size>" boot parameter.
112 Specify a huge page size. Used in conjunction with hugepages
120 specific huge page size. Valid huge page sizes are architecture
133 For example, on an architecture with 2M default huge page size::
150 Specify the default huge page size. This parameter can
156 architecture with 2M default huge page size::
163 huge page size is architecture dependent.
168 When multiple huge page sizes are supported, ``/proc/sys/vm/nr_hugepages``
176 huge page pool to 20, allocating or freeing huge pages, as required.
178 On a NUMA platform, the kernel will attempt to distribute the huge page pool
182 nodes with insufficient available, contiguous memory for a huge page will be
188 The success or failure of huge page allocation depends on the amount of
208 number of "surplus" huge pages from the kernel's normal page pool, when the
209 persistent huge page pool is exhausted. As these surplus huge pages become
210 unused, they are freed back to the kernel's normal page pool.
212 When increasing the huge page pool size via ``nr_hugepages``, any existing
215 the new persistent huge page pool size.
218 the default huge page size by setting the ``nr_hugepages`` sysctl to a
222 normal page pool.
224 Caveat: Shrinking the persistent huge page pool via ``nr_hugepages`` such that
232 With support for multiple huge page pools at run-time available, much of
233 the huge page userspace interface in ``/proc/sys/vm`` has been duplicated in
236 compatibility. The root huge page control directory in sysfs is::
240 For each huge page size supported by the running kernel, a subdirectory
258 The demote interfaces provide the ability to split a huge page into
260 1GB and 2MB huge pages sizes. A 1GB huge page can be split into 512
262 huge page size. The demote interfaces are:
265 is the size of demoted pages. When a page is demoted a corresponding
267 demote_size is set to the next smaller huge page size. If there are
268 multiple smaller huge page sizes, demote_size can be set to any of
269 these smaller sizes. Only huge page sizes less than the current huge
280 demote_size) function as described above for the default huge page-sized case.
284 Interaction of Task Memory Policy with Huge Page Allocation/Freeing
295 huge page pool, using the ``nr_hugepages`` example above, is::
311 resulting effect on persistent huge page allocation is as follows:
318 memory for a huge page, the allocation will not "fallback" to the nearest
320 undesirable imbalance in the distribution of the huge page pool, or
347 #. Boot-time huge page allocation attempts to distribute the requested number
353 A subset of the contents of the root huge page control directory in sysfs,
359 Under this directory, the subdirectory for each supported huge page size
377 applied, from which node the huge page allocation will be attempted.
409 If the platform supports multiple huge page sizes, the ``pagesize`` option can
410 be used to specify the huge page size and associated pool. ``pagesize``
412 default huge page size and associated pool will be used.
416 in bytes, or as a percentage of the specified huge page pool (``nr_hugepages``).
421 either bytes or a percentage of the huge page pool.
457 aligned to the native page size of the processor; they will normally fail with
460 a hugetlb page and the length is smaller than the hugepage size.
478 to help with huge page usability, environment setup, and control.