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 [212.227.17.190]) with ESMTPSA (Nemesis) id 1MVvL5-1x4ieR16M1-00NPx5; Thu, 08
 Oct 2026 14:29:02 +0200
Message-ID: <828fe52d7514cabf240f354268f7cfb541516f15.camel@gmx.de>
Subject: Re: [PATCH] sched/autogroup: Serialize nice rate-limit updates
From: Mike Galbraith <efault@gmx.de>
To: Hui Su <sh_def@163.com>, Ingo Molnar <mingo@redhat.com>, Peter Zijlstra
	 <peterz@infradead.org>
Cc: Juri Lelli <juri.lelli@redhat.com>, Vincent Guittot	
 <vincent.guittot@linaro.org>, Dietmar Eggemann <dietmar.eggemann@arm.com>, 
 Steven Rostedt <rostedt@goodmis.org>, Ben Segall <bsegall@google.com>, Mel
 Gorman <mgorman@suse.de>, Valentin Schneider <vschneid@redhat.com>, K
 Prateek Nayak <kprateek.nayak@amd.com>, 	linux-kernel@vger.kernel.org
Date: Thu, 08 Oct 2026 14:28:59 +0200
In-Reply-To: <20261008064440.240528-1-sh_def@163.com>
References: <20261008064440.240528-1-sh_def@163.com>
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On Thu, 2026-10-08 at 15:44 +0900, Hui Su wrote:
>=20
> - x86_64 KVM rate-limit oracle observed two pre-fix writes within 20 ms
> =C2=A0 and no post-fix pair within a 100 ms window.

The intent was to make it slow enough to prevent users from annoying
admins.  If it doesn't do that well enough, by all means lock it up.

	-Mike