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Appropriate for large allocations
A page is usually 4K, but can be made greater in some architectures
(sh, mips: 4, 8, 16 or 64K, but not configurable in i386 or arm).
Buddy allocator strategy, so only allocations of power of two number of pages are possible: 1 page, 2 pages, 4 pages, 8 pages, 16 pages, etc.
Typical maximum size is 8192 KB, but it might depend on the kernel configuration.
The allocated area is virtually contiguous (of course), but also physically contiguous. It is allocated in the identity-mapped part of the kernel memory space.
- This means that large areas may not be available or hard to retrieve due to physical memory fragmentation.