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Date: Sun, 16 Feb 2025 06:54:16 -1000
From: Tejun Heo <tj@kernel.org>
To: Andrea Righi <arighi@nvidia.com>
Cc: David Vernet <void@manifault.com>, Changwoo Min <changwoo@igalia.com>,
	Yury Norov <yury.norov@gmail.com>, Ingo Molnar <mingo@redhat.com>,
	Peter Zijlstra <peterz@infradead.org>,
	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>,
	Joel Fernandes <joel@joelfernandes.org>, Ian May <ianm@nvidia.com>,
	bpf@vger.kernel.org, linux-kernel@vger.kernel.org
Subject: Re: [PATCHSET v12 sched_ext/for-6.15] sched_ext: split global idle
 cpumask into per-NUMA cpumasks
Message-ID: <Z7IYOHDLVUTiYuI5@slm.duckdns.org>
References: <20250214194134.658939-1-arighi@nvidia.com>
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In-Reply-To: <20250214194134.658939-1-arighi@nvidia.com>

On Fri, Feb 14, 2025 at 08:39:59PM +0100, Andrea Righi wrote:
> = Overview =
> 
> As discussed during the sched_ext office hours, using a global cpumask to
> keep track of the idle CPUs can be inefficient and it may not scale really
> well on large NUMA systems.
> 
> Therefore, split the idle cpumask into multiple per-NUMA node cpumasks to
> improve scalability and performance on such large systems.
> 
> Scalability issues seem to be more noticeable on Intel Sapphire Rapids
> dual-socket architectures.

Applied 1-7 to sched_ext/for-6.15.

Thanks.

-- 
tejun