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Date:   Thu, 27 Apr 2023 15:21:30 +0300
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Subject: Re: [PATCH] nvme/tcp: Add support to set the tcp worker cpu affinity
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To:     Hannes Reinecke <hare@suse.de>, Li Feng <fengli@smartx.com>
Cc:     Keith Busch <kbusch@kernel.org>, Jens Axboe <axboe@fb.com>,
        Christoph Hellwig <hch@lst.de>,
        "open list:NVM EXPRESS DRIVER" <linux-nvme@lists.infradead.org>,
        linux-kernel <linux-kernel@vger.kernel.org>
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From:   Sagi Grimberg <sagi@grimberg.me>
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>>> Not saying that this should be a solution though.
>>>
>>> How many queues does your controller support that you happen to use
>>> queue 0 ?
>> Our controller only support one io queue currently.
> 
> Ouch.
> Remember, NVMe gets most of the performance improvements by using 
> several queues, and be able to bind the queues to cpu sets.
> Exposing just one queue will be invalidating any assumptions we do,
> and trying to improve interrupt steering won't work anyway.
> 
> I sincerely doubt we should try to 'optimize' for this rather peculiar 
> setup.

I tend to agree. This is not a common setup that I'm particularly
interested in exporting something dedicated in the driver for fiddling
with it...