Re: [PATCH] hugetlb: increase hugepage reservations when using node-specific "hugepages=" cmdline

[Andrew Morton <akpm@linux-foundation.org>]

On Thu, 22 Jan 2026 11:50:02 +0800 "Li Zhe" <lizhe.67@bytedance.com> wrote:

> Commit 3dfd02c90037 ("hugetlb: increase number of reserving hugepages
> via cmdline") raised the number of hugepages that can be reserved
> through the boot-time "hugepages=" parameter for the non-node-specific
> case, but left the node-specific form of the same parameter unchanged.
> 
> This patch extends the same optimization to node-specific reservations.
> When HugeTLB vmemmap optimization (HVO) is enabled and a node cannot
> satisfy the requested hugepages, the code first releases ordinary
> struct-page memory of hugepages obtained from the buddy allocator,
> allowing their struct-page memory to be reclaimed and reused for
> additional hugepage reservations on that node.
> 
> This is particularly beneficial for configurations that require
> identical, large per-node hugepage reservations. On a four-node, 384 GB
> x86 VM, the patch raises the attainable 2 MiB hugepage reservation from
> under 374 GB to more than 379 GB.
> 

Thanks.

I *think* the hugepages= documentation in
Documentation/admin-guide/mm/hugetlbpage.rst is still up to date and
complete, but can you please check it, see if there's somethig we should
do?