Re: [PATCH 5/5] mm: search from free_area_cache for the bigger size

From: Xiao Guangrong
Date: Thu Feb 02 2012 - 02:10:58 EST

On 02/02/2012 06:44 AM, Andrew Morton wrote:

> On Fri, 13 Jan 2012 19:47:31 +0800
> Xiao Guangrong <xiaoguangrong@xxxxxxxxxxxxxxxxxx> wrote:
>> If the required size is bigger than cached_hole_size, we would better search
>> from free_area_cache, it is more easier to get free region, specifically for
>> the 64 bit process whose address space is large enough
>> Do it just as hugetlb_get_unmapped_area_topdown() in arch/x86/mm/hugetlbpage.c
> Can this cause additional fragmentation of the virtual address region?
> If so, what might be the implications of this?

Hmm, i think it is not bad since we have cached_hole_size, and, this way is also
used in other functions and architectures(arch_get_unmapped_area,
hugetlb_get_unmapped_area_bottomup, hugetlb_get_unmapped_area_topdown......).

To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at
Please read the FAQ at