linux-kernel - Re: [RFC PATCH v3 0/6] Direct Map Removal for guest

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Message-ID: <4a015283-28e2-4459-825a-1fd542b81110@intel.com>
Date: Fri, 1 Nov 2024 12:39:21 -0700
From: Dave Hansen <dave.hansen@...el.com>
To: "Manwaring, Derek" <derekmn@...zon.com>
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Subject: Re: [RFC PATCH v3 0/6] Direct Map Removal for guest_memfd

On 11/1/24 12:29, Manwaring, Derek wrote:
> As far as performance, are you talking about just the fracturing or
> something beyond that? The data Mike brought to LSFMMBPF 2023 showed the
> perf impact from direct map fragmentation for memfd_secret isn't "that
> bad" [1].

Just the fracturing.

Mike's data are interesting, but I still think we're pretty far away
from saying that the kernel doesn't need large mappings.