From: Dave Chinner Subject: Re: Question about Experimental of Filesystem DAX. Date: Mon, 4 Jun 2018 13:51:18 +1000 Message-ID: <20180604035118.GN10363@dastard> References: <20180531112731.0CAC.E1E9C6FF@jp.fujitsu.com> <20180531150716.GA19764@linux.intel.com> <20180531174636.GA7825@magnolia> <20180531202556.GA28256@linux.intel.com> Mime-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Cc: Jan Kara , "Darrick J. Wong" , NVDIMM-ML , linux-xfs , Yasunori Goto , linux-ext4 To: Ross Zwisler Return-path: Content-Disposition: inline In-Reply-To: <20180531202556.GA28256-VuQAYsv1563Yd54FQh9/CA@public.gmane.org> List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Errors-To: linux-nvdimm-bounces-hn68Rpc1hR1g9hUCZPvPmw@public.gmane.org Sender: "Linux-nvdimm" List-Id: linux-ext4.vger.kernel.org On Thu, May 31, 2018 at 02:25:56PM -0600, Ross Zwisler wrote: > > Right, not a gating item for declaring DAX ready for prime time. > > Yep, I think that the very loud EXPERIMENTAL message is essentially telling > users "your data is at risk if you use this". And that's a call the filesystem maintainers need to make, not the DAX developers. It's clear from recent "oh fuck, DAX on XFS has stopped working in 4.17" a long time after after the changes that broke went into the mainline kernel indicates we have a serious testing problem here. i.e. that the filesystem developers who will have to maintain this stuff and deal with all the "DAX ate my data" bug reports haven't been testing DAX on their filesysetms at all in recent times. And that kinda says to me that the EXPERIMENTAL flag is not getting removed any time soon.... > As far as I know those are basically the 2 items on Dan's > list from a few mails ago (poison recovery & DMA vs truncate). FWIW, I have not been testing DAX because I'm waiting for infrastructure problems like DMA vs truncate to get fixed first.... Cheers, Dave. -- Dave Chinner david-FqsqvQoI3Ljby3iVrkZq2A@public.gmane.org