On 5:00 27/03, Matthew Wilcox wrote: > On Wed, Mar 27, 2019 at 06:00:52AM -0500, Goldwyn Rodrigues wrote: > > On 12:10 26/03, Matthew Wilcox wrote: > > > On Tue, Mar 26, 2019 at 02:02:47PM -0500, Goldwyn Rodrigues wrote: > > > > This sets S_DAX in inode->i_flags, which can be used with > > > > IS_DAX(). > > > > > > > > The dax option is restricted to non multi-device mounts. > > > > dax interacts with the device directly instead of using bio, so > > > > all bio-hooks which we use for multi-device cannot be performed > > > > here. While regular read/writes could be manipulated with > > > > RAID0/1, mmap() is still an issue. > > > > > > > > Auto-setting free space tree, because dealing with free space > > > > inode (specifically readpages) is a nightmare. > > > > Auto-setting nodatasum because we don't get callback for writing > > > > checksums after mmap()s. > > > > > > Congratulations on getting the bear to dance. But why? > > > > Why not ? ;) > > 18 files changed, 662 insertions(+), 77 deletions(-) > > I want to know what advantage we're getting for that. So the prime advantages are btrfs filesystem snapshots on the dax device. Leveraging btrfs features, reflinks works just as well. (In addition to all the advantages dax has to offer) -- Goldwyn
