Re: [RFC PATCH] blk-mq: fixup RESTART when queue becomes idle

[Jens Axboe <axboe@kernel.dk>]

On 1/18/18 3:35 PM, Laurence Oberman wrote:
> On Thu, 2018-01-18 at 22:24 +0000, Bart Van Assche wrote:
>> On Thu, 2018-01-18 at 17:18 -0500, Laurence Oberman wrote:
>>> OK, I ran 5 at once of 5 separate mount points.
>>> I am using 4k block sizes
>>> Its solid consistent for me. No stalls no gaps.
>>
>> Hi Laurence,
>>
>> That's great news and thank you for having shared this information
>> but I think
>> it should be mentioned that you have been running my tree in which
>> some recent
>> block and dm patches were reverted
>> (https://github.com/bvanassche/linux/tree/block-scsi-for-next)
>>
>>>
>>> [global]
>>> name=02-mq
>>> filename=fio-output-02-mq.txt
>>> rw=randwrite
>>> verify=md5
>>> ;rwmixread=60
>>> ;rwmixwrite=40
>>> bs=4K
>>> ;direct=1
>>> ;numjobs=4
>>> ;time_based=1
>>> runtime=120
>>>
>>> [file1]
>>> size=3G
>>> ioengine=libaio
>>> iodepth=16
>>>
>>> I watch I/O and I see it ramp up but fio still runs and it kind of
>>> shuts down.
>>
>> In test "file1" I see an I/O size of 3G. Does that mean that the
>> patch that
>> should fix the sgl_alloc() issue is working?
>>
>> Thanks,
>>
>> Bart.
> 
> Hello Bart Thank you.
> 
> OK, so booting into Mike tree now and then hopefully I get the lockups.
> Can you give me some idea of what to look for.
> I assume I/O just stops.
> 
> I want to get this happening in-house so we have an avenue to fix this.
> Following getting the stall I will attend to the slg patch test for the
> SRPT side.
> 
> Please note I am not running latest SRPT right now as you know.

When you do have a solid test case, please please submit a blktests
test case for it! This needs to be something we can regularly in
testing.

-- 
Jens Axboe