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Date:   Thu, 1 Mar 2018 23:03:30 +0800
From:   Ming Lei <ming.lei@redhat.com>
To:     Christoph Hellwig <hch@lst.de>
Cc:     Jianchao Wang <jianchao.w.wang@oracle.com>, axboe@fb.com,
        sagi@grimberg.me, linux-kernel@vger.kernel.org,
        linux-nvme@lists.infradead.org, keith.busch@intel.com
Subject: Re: [PATCH V2] nvme-pci: assign separate irq vectors for adminq and
 ioq0
Message-ID: <20180301150329.GB6795@ming.t460p>
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 <20180228164726.GB16536@lst.de>
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On Wed, Feb 28, 2018 at 05:47:26PM +0100, Christoph Hellwig wrote:
> Note that we originally allocates irqs this way, and Keith changed
> it a while ago for good reasons.  So I'd really like to see good
> reasons for moving away from this, and some heuristics to figure
> out which way to use.  E.g. if the device supports more irqs than
> I/O queues your scheme might always be fine.

If all CPUs for the 1st IRQ vector of admin queue are offline, then I
guess NVMe can't work any more.

So looks it is a good idea to make admin queue's IRQ vector assigned as
non-managed IRQs.

Thanks,
Ming