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Date: Sun, 26 Apr 2026 21:44:35 +0100
From: Matthew Wilcox <willy@infradead.org>
To: Jeff Layton <jlayton@kernel.org>
Cc: Alexander Viro <viro@zeniv.linux.org.uk>,
	Christian Brauner <brauner@kernel.org>, Jan Kara <jack@suse.cz>,
	Andrew Morton <akpm@linux-foundation.org>,
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Subject: Re: [PATCH v3 2/4] mm: kick writeback flusher for IOCB_DONTCACHE
 with targeted dirty tracking
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References: <20260426-dontcache-v3-0-79eb37da9547@kernel.org>
 <20260426-dontcache-v3-2-79eb37da9547@kernel.org>
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On Sun, Apr 26, 2026 at 07:56:08AM -0400, Jeff Layton wrote:
>   Mixed-mode noisy neighbor (dontcache writer + buffered readers):
>                        baseline    patched     change
>   writer (MB/s)         1297.6     1471.1     +13.4%
>   readers avg (MB/s)     855.0      462.4     -45.9%

hm.  This wasn't what I thought of when I thought of "noisy neighbour".
I'd have process A doing DONTCACHE writes to file A and process B doing
normal buffered writes to file B.