linux-kernel - Re: [PATCH 00/20] Add support for shared PTEs across processes

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Message-ID: <92f188ed-4f47-427b-b8fd-2c0f76ef129b@oracle.com>
Date: Tue, 28 Jan 2025 16:25:22 -0800
From: Anthony Yznaga <anthony.yznaga@...cle.com>
To: Andrew Morton <akpm@...ux-foundation.org>
Cc: willy@...radead.org, markhemm@...glemail.com, viro@...iv.linux.org.uk,
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Subject: Re: [PATCH 00/20] Add support for shared PTEs across processes


On 1/28/25 4:11 PM, Andrew Morton wrote:
> On Fri, 24 Jan 2025 15:54:34 -0800 Anthony Yznaga <anthony.yznaga@...cle.com> wrote:
>
>> Some of the field deployments commonly see memory pages shared
>> across 1000s of processes. On x86_64, each page requires a PTE that
>> is 8 bytes long which is very small compared to the 4K page
>> size.
> Dumb question: why aren't these applications using huge pages?
>
They often are using hugetlbfs but would also benefit from having page 
tables shared for other kinds of memory such as shmem, tmpfs or dax.