From: Christoph Hellwig <hch@infradead.org>
To: Barry Song <21cnbao@gmail.com>
Cc: akpm@linux-foundation.org, linux-mm@kvack.org, axboe@kernel.dk,
bala.seshasayee@linux.intel.com, chrisl@kernel.org,
david@redhat.com, hannes@cmpxchg.org,
kanchana.p.sridhar@intel.com, kasong@tencent.com,
nphamcs@gmail.com, ryan.roberts@arm.com,
senozhatsky@chromium.org, terrelln@fb.com,
usamaarif642@gmail.com, v-songbaohua@oppo.com,
wajdi.k.feghali@intel.com, willy@infradead.org,
ying.huang@linux.alibaba.com, yosryahmed@google.com,
baolin.wang@linux.alibaba.com
Subject: Re: [PATCH RFC] mm: map zero-filled pages to zero_pfn while doing swap-in
Date: Thu, 12 Dec 2024 00:29:38 -0800 [thread overview]
Message-ID: <Z1qe8v651uHPIy2L@infradead.org> (raw)
In-Reply-To: <20241212073711.82300-1-21cnbao@gmail.com>
On Thu, Dec 12, 2024 at 08:37:11PM +1300, Barry Song wrote:
> From: Barry Song <v-songbaohua@oppo.com>
>
> While developing the zeromap series, Usama observed that certain
> workloads may contain over 10% zero-filled pages. This may present
> an opportunity to save memory by mapping zero-filled pages to zero_pfn
> in do_swap_page(). If a write occurs later, do_wp_page() can
> allocate a new page using the Copy-on-Write mechanism.
Shouldn't this be done during, or rather instead of swap out instead?
Swapping all zero pages out just to optimize the in-memory
representation on seems rather backwards.
next prev parent reply other threads:[~2024-12-12 8:29 UTC|newest]
Thread overview: 10+ messages / expand[flat|nested] mbox.gz Atom feed top
2024-12-12 7:37 Barry Song
2024-12-12 8:29 ` Christoph Hellwig [this message]
2024-12-12 8:46 ` Barry Song
2024-12-12 8:50 ` Christoph Hellwig
2024-12-12 8:54 ` Barry Song
2024-12-12 8:50 ` David Hildenbrand
2024-12-12 9:16 ` Barry Song
2024-12-12 16:25 ` Johannes Weiner
2024-12-13 1:47 ` Barry Song
2024-12-13 2:27 ` Barry Song
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