Re: [PATCH 0/3] Provide more fine grained control over multipathing

From: Sagi Grimberg
Date: Wed Jun 06 2018 - 05:32:30 EST

We plan to implement all the fancy NVMe standards like ANA, but it
seems that there is still a requirement to let the host side choose
policies about how to use paths (round-robin vs least queue depth for
example). Even in the modern SCSI world with VPD pages and ALUA,
there are still knobs that are needed. Maybe NVMe will be different
and we can find defaults that work in all cases but I have to admit
I'm skeptical...

The sensible thing to do in nvme is to use different paths for
different queues.

Huh? different paths == different controllers so this sentence can't
be right... you mean that a path selector will select a controller
based on the home node of the local rdma device connecting to it and
the running cpu right?