From mboxrd@z Thu Jan  1 00:00:00 1970
From: Christoph Hellwig <hch-wEGCiKHe2LqWVfeAwA7xHQ@public.gmane.org>
Subject: Re: [PATCH 0/3] iopmem : A block device for PCIe memory
Date: Thu, 27 Oct 2016 05:32:19 -0700
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On Thu, Oct 27, 2016 at 01:22:49PM +0300, Sagi Grimberg wrote:
> Christoph, did you manage to leap to the future and solve the
> RDMA persistency hole? :)
> 
> e.g. what happens with O_DSYNC in this model? Or you did
> a message exchange for commits?

Yes, pNFS calls this the layoutcommit.  That being said once we get a RDMA
commit or flush operation we could easily make the layoutcommit optional
for some operations.  There already is a precedence for the in the
flexfiles layout specification.