Re: [LSF/MM TOPIC] Two blk-mq related topics

2018-02-07 Thread John Garry
On 30/01/2018 10:33, John Garry wrote: On 30/01/2018 01:24, Ming Lei wrote: On Mon, Jan 29, 2018 at 12:56:30PM -0800, James Bottomley wrote: On Mon, 2018-01-29 at 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

Re: [LSF/MM TOPIC] Two blk-mq related topics

2018-01-30 Thread Mel Gorman
On Tue, Jan 30, 2018 at 11:08:28AM +0100, Johannes Thumshirn wrote: > [+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? > >> > >> I'm

Re: [LSF/MM TOPIC] Two blk-mq related topics

2018-01-30 Thread John Garry
On 30/01/2018 01:24, Ming Lei wrote: On Mon, Jan 29, 2018 at 12:56:30PM -0800, James Bottomley wrote: On Mon, 2018-01-29 at 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

Re: [LSF/MM TOPIC] Two blk-mq related topics

2018-01-30 Thread Johannes Thumshirn
[+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? >> >> I'm not sure there's much to discuss ... I think the basic answer is as >> soon as

Re: [LSF/MM TOPIC] Two blk-mq related topics

2018-01-30 Thread Martin Steigerwald
Ming Lei - 30.01.18, 02:24: > > > SCSI_MQ is enabled on V3.17 firstly, but disabled at default. In > > > V4.13-rc1, it is enabled at default, but later the patch is reverted > > > in V4.13-rc7, and becomes disabled at default too. > > > > > > Now both the original reported PM issue(actually SCSI

Re: [LSF/MM TOPIC] Two blk-mq related topics

2018-01-29 Thread Jens Axboe
On 1/29/18 4:46 PM, James Bottomley wrote: > On Mon, 2018-01-29 at 14:00 -0700, Jens Axboe wrote: >> 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? >>> >>> I'm not sure there's

Re: [LSF/MM TOPIC] Two blk-mq related topics

2018-01-29 Thread Ming Lei
On Mon, Jan 29, 2018 at 03:40:31PM -0500, Mike Snitzer wrote: > On Mon, Jan 29 2018 at 10:46am -0500, > Ming Lei wrote: > > > 2. When to enable SCSI_MQ at default again? > > > > SCSI_MQ is enabled on V3.17 firstly, but disabled at default. In V4.13-rc1, > > it is enabled

Re: [LSF/MM TOPIC] Two blk-mq related topics

2018-01-29 Thread Ming Lei
On Mon, Jan 29, 2018 at 12:56:30PM -0800, James Bottomley wrote: > On Mon, 2018-01-29 at 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. I

Re: [LSF/MM TOPIC] Two blk-mq related topics

2018-01-29 Thread James Bottomley
On Mon, 2018-01-29 at 14:00 -0700, Jens Axboe wrote: > 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? > > > > I'm not sure there's much to discuss ... I think the basic

Re: [LSF/MM TOPIC] Two blk-mq related topics

2018-01-29 Thread Jens Axboe
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? > > 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

Re: [LSF/MM TOPIC] Two blk-mq related topics

2018-01-29 Thread James Bottomley
On Mon, 2018-01-29 at 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. > SCSI_MQ is enabled on V3.17 firstly, but disabled at default. In > V4.13-rc1,

Re: [LSF/MM TOPIC] Two blk-mq related topics

2018-01-29 Thread Mike Snitzer
On Mon, Jan 29 2018 at 10:46am -0500, Ming Lei wrote: > 2. When to enable SCSI_MQ at default again? > > SCSI_MQ is enabled on V3.17 firstly, but disabled at default. In V4.13-rc1, > it is enabled at default, but later the patch is reverted in V4.13-rc7, and > becomes

[LSF/MM TOPIC] Two blk-mq related topics

2018-01-29 Thread Ming Lei
Hi guys, Two blk-mq related topics 1. blk-mq vs. CPU hotplug & IRQ vectors spread on CPUs We have done three big changes in this field before, each time some issues are fixed, meantime new ones are introduced 1) freeze all queues during CPU hotplug handler - issues: queue dependency such as