From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Date: Wed, 31 Jan 2018 17:47:49 -0800 From: "Darrick J. Wong" To: Andiry Xu Cc: lsf-pc@lists.linux-foundation.org, Linux FS Devel , Linux MM , "linux-nvdimm@lists.01.org" , dan.j.williams@intel.com, david@fromorbit.com, willy@infradead.org, swanson@cs.ucsd.edu, jix024@cs.ucsd.edu Subject: Re: [LSF/MM TOPIC] Native NVMM file systems Message-ID: <20180201014749.GF4841@magnolia> References: MIME-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Disposition: inline Content-Transfer-Encoding: 8bit In-Reply-To: Sender: owner-linux-mm@kvack.org List-ID: On Wed, Jan 31, 2018 at 04:45:36PM -0800, Andiry Xu wrote: > PMEM/DAX should allow for significant improvements in file system > performance and enable new programming models that allow direct, > efficient access to PMEM from userspace. Achieving these gains in > existing file systems built for block devices (e.g., XFS and EXT4…) > presents a range of challenges (e.g., > https://lkml.org/lkml/2016/9/11/159) and has been the subject of a lot > of recent work on ext4 and xfs. > > An alternative is to build a NVMM-aware file system from scratch that > takes full advantage of the performance that PMEM offers and avoids > the complexity that block-based file systems include to maximize > performance on slow storage (e.g., relaxing atomicity constraints on > many operations). Of course, it also brings with it the complexity of > another file system. > > We recently sent out a patch set for one-such “clean slate” NVMM-aware > file system called NOVA. NOVA is log-structured DAX file system with > several nice features: That's the series that was sent out last August, correct? > * High performance, especially in metadata operations due to efficient > fine-grained logging > * High scalability with per-CPU memory pool and per-inode logging > * Strong metadata and data atomicity guarantees for all operations > * Full filesystem snapshot support with DAX-mmap > * Metadata replication/checksums and RAID-4 style data protection > > At the summit, we would like to discuss the trade-offs between > adapting NVMM features to existing file systems vs. creating/adopting > a purpose-built file system for NVMM. NOVA serves as useful starting > point for that discussion by demonstrating what’s possible. It may > also suggest some features that could be adapted to other file systems > to improve NVMM performance. > > We welcome people that are interested in file systems and NVM/DAX. > Particular people that would be useful to have in attendance are Dan > Williams, Dave Chinner, and Matthew Wilcox. I wouldn't mind being there too. :) --D > > Thanks, > Andiry -- 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