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Date:   Mon, 19 Jul 2021 03:31:51 +0100
From:   Matthew Wilcox <willy@infradead.org>
To:     Chanho Min <chanho.min@lge.com>
Cc:     Andrew Morton <akpm@linux-foundation.org>, linux-mm@kvack.org,
        linux-kernel@vger.kernel.org,
        "Kirill A . Shutemov" <kirill.shutemov@linux.intel.com>,
        Gunho Lee <gunho.lee@lge.com>, Juneho Choi <juno.choi@lge.com>,
        Inkyu Hwang <inkyu.hwang@lge.com>
Subject: Re: [PATCH] mm: make falutaround selectable
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References: <20210719010845.31898-1-chanho.min@lge.com>
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On Mon, Jul 19, 2021 at 10:08:45AM +0900, Chanho Min wrote:
> While faultaround can have performance gains, on certain platform it
> increases pss and causes swap to occur more frequently. This patch allows
> to unselect faultaround on platforms that do not want this behavior.

It would be better if we could determine the circumstances under which
faultaround is causing problems and automatically disable it without
asking the sysadmin to determine that.

Can you tell us more about the workload?