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Subject: Re: [PATCH] block: kyber: make kyber more friendly with merging
To:     Ming Lei <tom.leiming@gmail.com>
Cc:     Omar Sandoval <osandov@osandov.com>, Jens Axboe <axboe@kernel.dk>,
        linux-block <linux-block@vger.kernel.org>,
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From:   "jianchao.wang" <jianchao.w.wang@oracle.com>
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Date:   Wed, 30 May 2018 17:20:10 +0800
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Hi ming

On 05/30/2018 05:13 PM, Ming Lei wrote:
>> Yes, it maybe good for merging of 'none', because the rq_list is split into 3
>> lists, and not need to iterate the whole rq_list any more.
>> But what's about the dispatch when there is no io scheduler.
> blk_mq_flush_busy_ctxs() and blk_mq_dequeue_from_ctx() should work
> fine in case of 'none' if per-domain list is added to ctx. Then we can make
> none to be a bit fair on READ/WRITE.
> 

But how to determine when to dispatch READ, WRITE or other more, when there is no io scheduler ?

Thanks
Jianchao