From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: From: Johannes Thumshirn To: Jens Axboe Cc: James Bottomley , Ming Lei , lsf-pc@lists.linux-foundation.org, Linux-scsi@vger.kernel.org, linux-block@vger.kernel.org, linux-nvme@lists.infradead.org, Mel Gorman Subject: Re: [LSF/MM TOPIC] Two blk-mq related topics References: <20180129154455.GB17176@ming.t460p> <1517259390.3969.41.camel@HansenPartnership.com> Date: Tue, 30 Jan 2018 11:08:28 +0100 In-Reply-To: (Jens Axboe's message of "Mon, 29 Jan 2018 14:00:11 -0700") Message-ID: MIME-Version: 1.0 Content-Type: text/plain; charset=utf-8 List-ID: [+Cc Mel] Jens Axboe writes: > On 1/29/18 1:56 PM, James Bottomley wrote: >> On Mon, 2018-01-29 at 23:46 +0800, Ming Lei wrote: >> [...] >>> 2. When to enable SCSI_MQ at default again? >>=20 >> I'm not sure there's much to discuss ... I think the basic answer is as >> soon as Christoph wants to try it again. > > FWIW, internally I've been running various IO intensive workloads on > what is essentially 4.12 upstream with scsi-mq the default (with > mq-deadline as the scheduler) and comparing IO workloads with a > previous 4.6 kernel (without scsi-mq), and things are looking > great. > > We're never going to iron out the last kinks with it being off > by default, I think we should attempt to flip the switch again > for 4.16. The 4.12 sounds interesting. I remember Mel ran some test with 4.12 as we where considering to flip the config option for SLES and it showed several road blocks. I'm not sure whether he re-evaluated 4.13/4.14 on his grid though. But I'm definitively interested in this discussion and can even possibly share some benchmark results we did in our FC Lab. Byte, Johannes --=20 Johannes Thumshirn Storage jthumshirn@suse.de +49 911 74053 689 SUSE LINUX GmbH, Maxfeldstr. 5, 90409 N=C3=BCrnberg GF: Felix Imend=C3=B6rffer, Jane Smithard, Graham Norton HRB 21284 (AG N=C3=BCrnberg) Key fingerprint =3D EC38 9CAB C2C4 F25D 8600 D0D0 0393 969D 2D76 0850