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Date: Mon, 3 Aug 2026 05:43:59 -1000
From: Keith Busch <kbusch@kernel.org>
To: Thomas Gleixner <tglx@linutronix.de>
Cc: santhosh kumar <santhu.linux@gmail.com>, linux-kernel@vger.kernel.org,
	Christoph Hellwig <hch@lst.de>, Ming Lei <ming.lei@redhat.com>,
	x86@kernel.org
Subject: Re: [RFC] PCI_IRQ_AFFINITY limits MSI-X allocation on 384 CPU /
 1000+ NVMe system
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On Thu, Jul 30, 2026 at 09:44:21PM +0200, Thomas Gleixner wrote:
> On Thu, Jul 30 2026 at 07:28, Keith Busch wrote:
> > We can introduce a module parameter to throttle down the maximum number
> > of IO queues to allocate per controller. I don't think the driver can
> > automatically reason out what the correct number should be because it
> > doesn't know how many devices it's going to see.
> 
> I might be missing something here as usual, but the number of io queues
> per controller does not affect that at all as I explained before.

Oh, you did explain that. I skipped to the end as I had too many
distractions last week. Sorry about that, and thanks for the
re-explanation.

I mistakenly was thinking the effective_affinity was the only hardware
resource used. Back to the drawing board.