From: "David Hildenbrand (Arm)" <david@kernel.org>
To: Muchun Song <songmuchun@bytedance.com>,
Andrew Morton <akpm@linux-foundation.org>
Cc: yinghai@kernel.org, Muchun Song <muchun.song@linux.dev>,
Lorenzo Stoakes <ljs@kernel.org>,
"Liam R. Howlett" <Liam.Howlett@oracle.com>,
Vlastimil Babka <vbabka@kernel.org>,
Mike Rapoport <rppt@kernel.org>,
Suren Baghdasaryan <surenb@google.com>,
Michal Hocko <mhocko@suse.com>,
linux-mm@kvack.org, linux-kernel@vger.kernel.org
Subject: Re: [RFC PATCH] mm/sparse: remove sparse_buffer
Date: Wed, 8 Apr 2026 15:40:21 +0200 [thread overview]
Message-ID: <b22f0af1-848d-45da-99b2-0c28b740e979@kernel.org> (raw)
In-Reply-To: <20260407083951.2823915-1-songmuchun@bytedance.com>
On 4/7/26 10:39, Muchun Song wrote:
> The sparse_buffer was originally introduced in commit 9bdac9142407
> ("sparsemem: Put mem map for one node together.") to allocate a
> contiguous block of memory for all memmaps of a NUMA node.
>
> However, the original commit message did not clearly state the actual
> benefits or the necessity of keeping all memmap areas strictly
> contiguous for a given node.
We don't want the memmap to be scattered around, given that it is one of
the biggest allocations during boot.
It's related to not turning too many memory blocks/sections
un-offlinable I think.
I always imagined that memblock would still keep these allocations close
to each other. Can you verify if that is indeed true?
--
Cheers,
David
prev parent reply other threads:[~2026-04-08 13:40 UTC|newest]
Thread overview: 2+ messages / expand[flat|nested] mbox.gz Atom feed top
2026-04-07 8:39 Muchun Song
2026-04-08 13:40 ` David Hildenbrand (Arm) [this message]
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