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Date: Mon, 27 May 2024 12:46:14 +0900
From: Byungchul Park <byungchul@sk.com>
To: Dave Hansen <dave.hansen@intel.com>
Cc: linux-kernel@vger.kernel.org, linux-mm@kvack.org,
	kernel_team@skhynix.com, akpm@linux-foundation.org,
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	dave.hansen@linux.intel.com, rjgolo@gmail.com
Subject: Re: [PATCH v10 00/12] LUF(Lazy Unmap Flush) reducing tlb numbers
 over 90%
Message-ID: <20240527034614.GA12937@system.software.com>
References: <20240510065206.76078-1-byungchul@sk.com>
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On Sun, May 26, 2024 at 07:43:10PM -0700, Dave Hansen wrote:
> On 5/26/24 18:57, Byungchul Park wrote:
> ...
> > Plus, I will add another give-up at code changing the permission of vma
> > to writable.
> 
> I suspect you have a much more general problem on your hands. Just
> tweaking the VFS or mmap() code likely isn't going to cut it.

LUF is interested in limited folios that are migratable or reclaimable
in lru for now.  So, IMHO, fixing a few things is going to cut it.

> I guess we'll see what you come up with next, but this email was really
> just the result of Vlastimil and I chatting on IRC for five minutes
> about this set.
> 
> It has absolutely not been tested nor reviewed enough.  <fud>I hope the
> performance gains stick around once more of the bugs are gone.</fud>

Sure. It should be.

	Byungchul