From mboxrd@z Thu Jan 1 00:00:00 1970 From: jthumshirn@suse.de (Johannes Thumshirn) Date: Tue, 30 Jan 2018 11:08:28 +0100 Subject: [LSF/MM TOPIC] Two blk-mq related topics In-Reply-To: (Jens Axboe's message of "Mon, 29 Jan 2018 14:00:11 -0700") References: <20180129154455.GB17176@ming.t460p> <1517259390.3969.41.camel@HansenPartnership.com> Message-ID: [+Cc Mel] Jens Axboe writes: > On 1/29/18 1:56 PM, James Bottomley wrote: >> On Mon, 2018-01-29@23:46 +0800, Ming Lei wrote: >> [...] >>> 2. When to enable SCSI_MQ at default again? >> >> 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 -- Johannes Thumshirn Storage jthumshirn at suse.de +49 911 74053 689 SUSE LINUX GmbH, Maxfeldstr. 5, 90409 N?rnberg GF: Felix Imend?rffer, Jane Smithard, Graham Norton HRB 21284 (AG N?rnberg) Key fingerprint = EC38 9CAB C2C4 F25D 8600 D0D0 0393 969D 2D76 0850