Re: [PATCH RFC 09/22] block, cfq: replace CFQ with the BFQ-v0 I/O scheduler

From: Nikolay Borisov
Date: Fri Mar 11 2016 - 06:24:39 EST

On 03/11/2016 01:17 PM, Christoph Hellwig wrote:
> On Sat, Mar 05, 2016 at 07:18:30PM +0700, Linus Walleij wrote:
>> Depends on what time horizon and target I'd say. Paolo was in contact with
>> the MMC/SD subsystem maintainer Ulf Hansson. (e)MMC/SD are both
>> synchronous command-response-based protocols, and as of today
>> single-channel. So everone's smartphone and tablet etc are today
>> single-channel. I don't know if there is even a protocol change coming
>> to augment this, the only duct-tapeish solution I've heard about is
>> command queueing which is basically a kind of pipelining of requests.
> We use blkj-mq for single queue devices as well, in fact most consumers
> are single queue. MMC is a prime candidate that hould move over soon.

Out of curiosity - would it make sense to have something like BFQ/CFQ
for single-queue blk-mq users?