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Date: Tue, 21 May 2024 10:31:59 +0800
From: Ming Lei <ming.lei@redhat.com>
To: Christoph Hellwig <hch@lst.de>
Cc: Thomas Gleixner <tglx@linutronix.de>, Keith Busch <kbusch@kernel.org>,
	Keith Busch <kbusch@meta.com>, linux-nvme@lists.infradead.org,
	linux-kernel@vger.kernel.org
Subject: Re: [PATCH 2/2] nvme-pci: allow unmanaged interrupts
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On Mon, May 20, 2024 at 05:37:42PM +0200, Christoph Hellwig wrote:
> On Sun, May 12, 2024 at 08:35:55AM +0200, Thomas Gleixner wrote:
> > That's expected as you pin the I/O operation on the isolated CPUs which
> > in turn makes them use the per CPU queue.
> > 
> > The isolated CPUs are only excluded for device management interrupts,
> > but not for the affinity spread of the queues.
> 
> We'll probably need a version of isolcpus that also excludes the
> interrupt spread given that users are asking for it.  And I'd much
> prefer that over adding radom module options to every driver to disable
> managed interrupts.

BTW, isolcpus has been marked as deprecated, and it can't be adjust
runtime.

isolcpus=	[KNL,SMP,ISOL] Isolate a given set of CPUs from disturbance.
			[Deprecated - use cpusets instead]


Thanks, 
Ming