From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: From: Jeff Moyer To: Christoph Hellwig Cc: "Darrick J. Wong" , Ross Zwisler , lsf-pc@lists.linux-foundation.org, linux-fsdevel@vger.kernel.org, linux-nvdimm@ml01.01.org, linux-block@vger.kernel.org, linux-mm@kvack.org Subject: Re: [LSF/MM TOPIC] Future direction of DAX References: <20170114002008.GA25379@linux.intel.com> <20170114082621.GC10498@birch.djwong.org> <20170117015033.GD10498@birch.djwong.org> <20170117075735.GB19654@infradead.org> <20170117150638.GA3747@infradead.org> Date: Tue, 17 Jan 2017 11:07:14 -0500 In-Reply-To: <20170117150638.GA3747@infradead.org> (Christoph Hellwig's message of "Tue, 17 Jan 2017 07:06:38 -0800") Message-ID: MIME-Version: 1.0 Content-Type: text/plain Sender: owner-linux-mm@kvack.org List-ID: Christoph Hellwig writes: > On Tue, Jan 17, 2017 at 09:54:27AM -0500, Jeff Moyer wrote: >> I spoke with Dave before the holidays, and he indicated that >> PMEM_IMMUTABLE would be an acceptable solution to allowing applications >> to flush data completely from userspace. I know this subject has been >> beaten to death, but would you mind just summarizing your opinion on >> this one more time? I'm guessing this will be something more easily >> hashed out at LSF, though. > > Come up with a prototype that doesn't suck and allows all fs features to > actually work. OK, I'll take this to mean that PMEM_IMMUTABLE is a non-starter. Perhaps synchronous page faults (or whatever you want to call it) would work, but... > And show an application that actually cares and shows benefits on > publicly available real hardware. This is the crux of the issue. > Until then go away and stop wasting everyones time. Fair enough. It seems fairly likely that this sort of functionality would provide a big benefit. But I agree we should have a real-world use case as proof. Thanks, Jeff -- To unsubscribe, send a message with 'unsubscribe linux-mm' in the body to majordomo@kvack.org. For more info on Linux MM, see: http://www.linux-mm.org/ . Don't email: email@kvack.org