Re: [PATCH 00/14] introduce the BFQ-v0 I/O scheduler as an extra scheduler

[Jan Kara]

On Wed 26-10-16 03:19:03, Christoph Hellwig wrote:
> Just as last time:
> 
> big NAK for introducing giant new infrastructure like a new I/O scheduler
> for the legacy request structure.
> 
> Please direct your engergy towards blk-mq instead.

Christoph, we will probably talk about this next week but IMO rotating
disks and SATA based SSDs are going to stay with us for another 15 years,
likely more. For them blk-mq is no win, relatively complex IO scheduling
like CFQ or BFQ does is a big win for them in some cases. So I think IO
scheduling (and thus place for something like BFQ) is going to stay with us
for quite a long time still. So are we going to add hooks in blk-mq to
support full-blown IO scheduling at least for single queue devices? Or how
else do we want to support that HW?

								Honza
-- 
Jan Kara <jack@xxxxxxxx>
SUSE Labs, CR