On 14/03/2013 02:05, Theodore Ts'o wrote: > Just as a note, e2fsck -v can sometimes get this information much more > quickly than other alternatives, since it can scan the file system in > inode order, instead of the essentially random order. > > Just as a side, if you just want to get a rough count of the number of > directories, you can get that by grabbing the information out of > dumpe2fs. Very useful. Global stats without having to scan the whole filesystems are very precious... I was wondering : couldn't we use dumpe2fs or something based on libext2fs to quickly extract a snapshot of all inodes from a given filesystem ? For incremental backups, simply checking the mtime on millions of inodes and discovering that only a handful of them were updated since the previous pass looks very inefficient with readdir()+lstat(). So mnay syscalls, so man spoonfed bits of information. When I had a peek, I tought I'd got a list of inodes but would not be able to link them back to their name(s) without inducing the same cost as a regular find-like filesystem traversal. Does it make sense ? AFAIK I would be better served with block-level snapshot solutions, but LVM snapshots are supposed to double your writes if I got it right, and I'm not sure there's something else in the Linux and free software world. Plus I'd love to not migrate away from my ext3/4's without a compelling reason. Btrfs is not (yet) and option and ZFS doesn't fit legally with Linux. _______________________________________________ Ext3-users mailing list Ext3-users@xxxxxxxxxx https://www.redhat.com/mailman/listinfo/ext3-users
