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Diffstat (limited to 'Documentation/vm/hugetlbpage.txt')
| -rw-r--r-- | Documentation/vm/hugetlbpage.txt | 23 |
1 files changed, 14 insertions, 9 deletions
diff --git a/Documentation/vm/hugetlbpage.txt b/Documentation/vm/hugetlbpage.txt index 457634c1e03..bdd4bb97fff 100644 --- a/Documentation/vm/hugetlbpage.txt +++ b/Documentation/vm/hugetlbpage.txt @@ -72,7 +72,7 @@ number of huge pages requested. This is the most reliable method of allocating huge pages as memory has not yet become fragmented. Some platforms support multiple huge page sizes. To allocate huge pages -of a specific size, one must preceed the huge pages boot command parameters +of a specific size, one must precede the huge pages boot command parameters with a huge page size selection parameter "hugepagesz=<size>". <size> must be specified in bytes with optional scale suffix [kKmMgG]. The default huge page size may be selected with the "default_hugepagesz=<size>" boot parameter. @@ -165,6 +165,7 @@ which function as described above for the default huge page-sized case. Interaction of Task Memory Policy with Huge Page Allocation/Freeing +=================================================================== Whether huge pages are allocated and freed via the /proc interface or the /sysfs interface using the nr_hugepages_mempolicy attribute, the NUMA @@ -229,6 +230,7 @@ resulting effect on persistent huge page allocation is as follows: of huge pages over all on-lines nodes with memory. Per Node Hugepages Attributes +============================= A subset of the contents of the root huge page control directory in sysfs, described above, will be replicated under each the system device of each @@ -258,6 +260,7 @@ applied, from which node the huge page allocation will be attempted. Using Huge Pages +================ If the user applications are going to request huge pages using mmap system call, then it is required that system administrator mount a file system of @@ -296,14 +299,16 @@ calls, though the mount of filesystem will be required for using mmap calls without MAP_HUGETLB. For an example of how to use mmap with MAP_HUGETLB see map_hugetlb.c. -******************************************************************* +Examples +======== -/* - * hugepage-shm: see Documentation/vm/hugepage-shm.c - */ +1) map_hugetlb: see tools/testing/selftests/vm/map_hugetlb.c -******************************************************************* +2) hugepage-shm: see tools/testing/selftests/vm/hugepage-shm.c -/* - * hugepage-mmap: see Documentation/vm/hugepage-mmap.c - */ +3) hugepage-mmap: see tools/testing/selftests/vm/hugepage-mmap.c + +4) The libhugetlbfs (http://libhugetlbfs.sourceforge.net) library provides a + wide range of userspace tools to help with huge page usability, environment + setup, and control. Furthermore it provides useful test cases that should be + used when modifying code to ensure no regressions are introduced. |