From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from ipmail06.adl6.internode.on.net (ipmail06.adl6.internode.on.net [150.101.137.145]) by ml01.01.org (Postfix) with ESMTP id EF708201B0458 for ; Fri, 22 Feb 2019 15:11:44 -0800 (PST) Date: Sat, 23 Feb 2019 10:11:36 +1100 From: Dave Chinner Subject: Re: [RFC PATCH] pmem: advertise page alignment for pmem devices supporting fsdax Message-ID: <20190222231136.GC23020@dastard> References: <20190222182008.GT6503@magnolia> MIME-Version: 1.0 Content-Disposition: inline In-Reply-To: <20190222182008.GT6503@magnolia> List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Errors-To: linux-nvdimm-bounces@lists.01.org Sender: "Linux-nvdimm" To: "Darrick J. Wong" Cc: linux-nvdimm@lists.01.org, xfs , zwisler@kernel.org, linux-fsdevel List-ID: On Fri, Feb 22, 2019 at 10:20:08AM -0800, Darrick J. Wong wrote: > Hi all! > > Uh, we have an internal customer who's been trying out MAP_SYNC > on pmem, and they've observed that one has to do a fair amount of > legwork (in the form of mkfs.xfs parameters) to get the kernel to set up > 2M PMD mappings. They (of course) want to mmap hundreds of GB of pmem, > so the PMD mappings are much more efficient. > > I started poking around w.r.t. what mkfs.xfs was doing and realized that > if the fsdax pmem device advertised iomin/ioopt of 2MB, then mkfs will > set up all the parameters automatically. Below is my ham-handed attempt > to teach the kernel to do this. What's the before and after mkfs output? (need to see the context that this "fixes" before I comment) Cheers, Dave. -- Dave Chinner david@fromorbit.com _______________________________________________ Linux-nvdimm mailing list Linux-nvdimm@lists.01.org https://lists.01.org/mailman/listinfo/linux-nvdimm