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Date:   Mon, 4 Jun 2018 09:18:29 +0200
From:   Johannes Thumshirn <jthumshirn@suse.de>
To:     Hannes Reinecke <hare@suse.de>
Cc:     Jens Axboe <axboe@kernel.dk>, Mike Snitzer <snitzer@redhat.com>,
        Christoph Hellwig <hch@lst.de>,
        Linus Torvalds <torvalds@linux-foundation.org>,
        "Martin K. Petersen" <martin.petersen@oracle.com>,
        Linux NVMe Mailinglist <linux-nvme@lists.infradead.org>,
        Laurence Oberman <loberman@redhat.com>,
        Sagi Grimberg <sagi@grimberg.me>,
        James Smart <james.smart@broadcom.com>,
        Ewan Milne <emilne@redhat.com>,
        Linux Kernel Mailinglist <linux-kernel@vger.kernel.org>,
        Keith Busch <keith.busch@intel.com>,
        Martin George <marting@netapp.com>,
        John Meneghini <John.Meneghini@netapp.com>,
        dm-devel@redhat.com, mwilck@suse.de
Subject: Re: [PATCH 0/3] Provide more fine grained control over multipathing
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On Mon, Jun 04, 2018 at 08:19:21AM +0200, Hannes Reinecke wrote:
> Without it we're having a choice of disappointing (paying) customers or
> disappointing the upstream community.

I personally think (regardless of the fact, that I wrote the patch
under discussion), using the module parameter is sufficient for these
kind of customers. For me it's an either/or kind of setting (either
native or dm-mpath).

Downstream distributions could still carry a small patch flipping the
default to off if they want to maintain backwards compatibility with
existing dm-mpath setups (which for NVMe I doubt there are many!).

What we really should do is, try to give multipath-tools a 'nvme
list-subsys' like view of nvme native multipathing (and I think Martin
W. has already been looking into this a while ago).


   Johannes
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Johannes Thumshirn                                          Storage
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