GET_HUGE_PAGES(3)

💖 GET_HUGE_PAGES(3) 💖

okay bestie, welcome to the GET_HUGE_PAGES(3) manual page, aka the Library Functions Manual glow-up you didn't know you needed ✨

🌸 NAME 🌸

get_huge_pages, free_huge_pages — Allocate and free hugepages 🫶

✨ SYNOPSIS ✨

#include <hugetlbfs.h>

void *get_huge_pages(size_t len, ghp_t flags);
void free_huge_pages(void *ptr);

💅 DESCRIPTION 💅

so like, get_huge_pages() allocates a memory region len bytes in size backed by hugepages. no cap. 🦋

hugepages may be of benefit to applications that use large amounts of address space and suffer a performance hit due to TLB misses. lowkey iconic. Wall-clock time or oprofile can be used to determine if there is a performance benefit from using hugepages or not. like, do your research bestie 🔍

the len parameter must be hugepage-aligned, fr fr. and in the current implementation, only the default hugepage size may be allocated via this function 👑 use gethugepagesize to discover what the alignment should be.

the flags argument changes the behaviour of the function. flags may be or'd together 🎀

• GHP_DEFAULT — Allocate a region of memory of the requested length backed by hugepages of the default hugepage size. Return NULL if sufficient pages are not available 😭

free_huge_pages() frees a region of memory allocated by get_huge_pages(). 💖

⚠️ bestie the behaviour of the function if another pointer is used, valid or otherwise, is undefined. undefined behaviour is not the vibe. do not do it. periodt 💀

🌈 RETURN VALUE 🌈

On success, a pointer is returned to the allocated memory 🎉 On error, NULL is returned. errno will be set based on what the failure of mmap() was due to. yeah she's giving "blame the syscall" energy 🙈

🦋 SEE ALSO 🦋

• oprofile(1)
• gethugepagesize(3)
• get_hugepage_region(3)
• libhugetlbfs(7)

🎀 AUTHORS 🎀

libhugetlbfs was written by various people on the libhugetlbfs-devel mailing list. shoutout to the whole group chat 💜

and that's the whole page, bestie — this one dropped way back on October 8, 2008, and it lives in the GET_HUGE_PAGES(3) section of the manual. slay 💅✨