[RFC] nvme-mpath: delete disk after last connection

[Hannes Reinecke]

On 9/29/20 8:16 PM, Sagi Grimberg wrote:
> 
>>> Something here is not clear to me, we are not really talking about "all
>>> paths down" but rather "all paths lost", which should take the gendisk
>>> down AFAIK.
>>>
>>> Keith, shouldn't we modify the gendisk reference manipulation in
>>> nvme_mpath_remove_disk instead of moving it to the call sites?
>>>
>>> I'm still unsure why we need a timer for this. If a path is removed
>>> (e.g. disconnected, we shouldn't keep the gendisk up).
>>
>> True.  And I guess the right place to deal with timers is on how long
>> we are going to keep retrying (or at least the underlying disks alive).
> 
> Which is orthogonal to this specific patch right?
> 
> As for timers, I wouldn't want to introduce a modparam for that. Perhaps
> the correct way to do this is with what Victor suggested where mpath
> fastfail is really the longest controller fastfail...

Yes. If we're talking timers we should be looking a fastfail, as this is 
really what we want here.

Cheers,

Hannes
-- 
Dr. Hannes Reinecke                Kernel Storage Architect
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