On Wed, Jan 31, 2018 at 4:45 PM, Andiry Xu <andiry@xxxxxxxxx> 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: > > * 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. The rest of the fs-dax crew would also be useful to have: Jan Kara Ross Zwisler -- To unsubscribe, send a message with 'unsubscribe linux-mm' in the body to majordomo@xxxxxxxxx. For more info on Linux MM, see: http://www.linux-mm.org/ . Don't email: <a href
