On Thu, Feb 16, 2017@01:21:29PM -0500, Mike Snitzer wrote:

multipath-tools has tables that specify all the defaults for a given
target backend.  NVMe will just be yet another.

No, if we get things right it won't.  ALUA already got rid of most
of the parameter people would have to set under normal conditions,
and I plan to make sure the NVMe equivalent will do it for all
parameters.  I am active in the NVMe working group and will do my
best to get there.  There's a few others folks here that are more or
less active there as well (Keith, Martin, Jens for example), so I
think we have a chance.

That beeing said Keith is right that we'll always have odd setups
where we need to overrid things, and we will have to provide tunables
for that.  It's no different from any other kernel subsystem in that.