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

[Johannes Thumshirn]

[+Cc Mel]
Jens Axboe <axboe at kernel.dk> 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 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
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