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Date: Mon, 27 Jan 2025 17:18:57 -0800
From: Andrew Morton <akpm@linux-foundation.org>
To: Michal Clapinski <mclapinski@google.com>
Cc: Vlastimil Babka <vbabka@suse.cz>, Pasha Tatashin <tatashin@google.com>,
 linux-mm@kvack.org, linux-kernel@vger.kernel.org
Subject: Re: [PATCH v3 2/2] mm/compaction: make proactive compaction high
 watermark configurable via sysctl
Message-Id: <20250127171857.34c71d3a6f0cde1953b02a58@linux-foundation.org>
In-Reply-To: <20250127215020.4023545-3-mclapinski@google.com>
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On Mon, 27 Jan 2025 22:50:20 +0100 Michal Clapinski <mclapinski@google.com> wrote:

> Currently, the difference between the high and low watermarks for
> proactive compaction is hardcoded to 10. This hardcoded difference is
> too large for free page reporting to work well.
> 
> Add a new sysctl, `compaction_proactiveness_leeway`, to control the
> difference between the high and low watermarks.
> 

Oh dear, yet another tunable.  Is there any way in which we can
acceptably improve the kernel without adding this?