On Tue, Jan 07, 2020 at 12:12:00PM +0200, Amir Goldstein wrote: > On Tue, Jan 7, 2020 at 10:36 AM Hugh Dickins <hughd@xxxxxxxxxx> wrote: > > > > On Tue, 7 Jan 2020, Amir Goldstein wrote: > > > On Tue, Jan 7, 2020 at 2:40 AM Dave Chinner <david@xxxxxxxxxxxxx> wrote: > > > > On Tue, Jan 07, 2020 at 12:16:43AM +0000, Chris Down wrote: > > > > > Dave Chinner writes: > > > > > > It took 15 years for us to be able to essentially deprecate > > > > > > inode32 (inode64 is the default behaviour), and we were very happy > > > > > > to get that albatross off our necks. In reality, almost everything > > > > > > out there in the world handles 64 bit inodes correctly > > > > > > including 32 bit machines and 32bit binaries on 64 bit machines. > > > > > > And, IMNSHO, there no excuse these days for 32 bit binaries that > > > > > > don't using the *64() syscall variants directly and hence support > > > > > > 64 bit inodes correctlyi out of the box on all platforms. > > > > Interesting take on it. I'd all along imagined we would have to resort > > to a mount option for safety, but Dave is right that I was too focused on > > avoiding tmpfs regressions, without properly realizing that people were > > very unlikely to have written such tools for tmpfs in particular, but > > written them for all filesystems, and already encountered and fixed > > such EOVERFLOWs for other filesystems. > > > > Hmm, though how readily does XFS actually reach the high inos on > > ordinary users' systems? > > > > Define 'ordinary' > I my calculations are correct, with default mkfs.xfs any inode allocated > from logical offset > 2TB on a volume has high ino bits set. > Besides, a deployment with more than 4G inodes shouldn't be hard to find. You don't need to allocate 4 billion inodes to get >32bit inodes in XFS - the inode number is an encoding of the physical location of the inode in the filesystem. Hence we just have to allocate the inode at a disk address higher than 2TB into the device and we overflow 32bits. e.g. make a sparse fs image file of 10TB, mount it, create 50 subdirs, then start creating zero length files spread across the 50 separate subdirectories. You should see >32bit inode numbers almost immediately. (i.e. as soon as we allocate inodes in AG 2 or higher) IOWs, there are *lots* of 64bit inode numbers out there on XFS filesystems.... Cheers, Dave. -- Dave Chinner david@xxxxxxxxxxxxx
