On Thu, Oct 29, 2020 at 6:29 PM Oscar Salvador <osalvador@xxxxxxx> wrote: > > On Mon, Oct 26, 2020 at 10:50:58PM +0800, Muchun Song wrote: > > The purpose of introducing HUGETLB_PAGE_FREE_VMEMMAP is to configure > > whether to enable the feature of freeing unused vmemmap associated > > with HugeTLB pages. Now only support x86. > > Why this needs to be a config thing? > If this space-memory-optimization does not come with a trade-off, > why does the user have to set this instead of coming by default? Now we only support x86_64. If we want to support other archs. We need some arch special code to support this feature. In the future, if this patch series is merged to mainline, I will implement this optimization for other archs. At that time we can remove the HUGETLB_PAGE_FREE_VMEMMAP. Thanks. > > > -- > Oscar Salvador > SUSE L3 -- Yours, Muchun