Date: Thu, 23 Oct 2014 09:32:29 -0400
To: Chuck Lever <chuck.lever@oracle.com>
Cc: Trond Myklebust <trond.myklebust@primarydata.com>,
        Anna Schumaker <Anna.Schumaker@netapp.com>,
        Linux NFS Mailing List <linux-nfs@vger.kernel.org>,
        Tom Talpey <tom@talpey.com>
Subject: Re: [PATCH v1 13/16] NFS: Add sidecar RPC client support
Message-ID: <20141023133229.GA16717@fieldses.org>
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From: "J. Bruce Fields" <bfields@fieldses.org>
Sender: linux-nfs-owner@vger.kernel.org

On Tue, Oct 21, 2014 at 01:11:26PM -0400, Chuck Lever wrote:
> The size of the changeset _is_ the justification. It’s
> a much less invasive change to add a TCP side-car than
> it is to implement RDMA backchannel on both server and
> client.

Something I'm confused about: is bidirectional RPC/RDMA optional or
mandatory for servers to implement?

Something somewhere has to be mandatory if we want to guarantee a
working backchannel between any two implementations.

--b.