My first post to lkml so please go easy on me :). After mkfs.ext4 on a 20TB volume, the process ext4lazyinit is now grinding away on the disks for several hours, and potentially days more according to other threads I've read. By design it is using very little I/O (500-1000 K/s) even though the volume is capable of 200-500 MB/s and the system is doing nothing ATM. The constant grinding noise (with HDD's) that this causes is disruptive in a home or office environment. Lazy init may also cause undue worry to users running systems 'at home' - "could the fs get corrupted if power goes out while lazy init is going on?" As I understand: * There is no way to monitor its % completion * There is no way to force it to speed up * Would require a reformat to disable the lazy feature If I knew I would have disabled lazy init during mkfs but now I've copied TB's of data to the drive and would much rather not have to start over. Would suggest either a clear warning at mkfs ("using lazy init by default...") or default lazy init to off. Defaulting to off will cause the least surprise to most Linux users. For those who have some real issue with the standard upfront init times they can easily search for and enable the lazy init feature. Personally have never had an issue with upfront init even on 10-30 TB volumes. Enterprises with PB volumes can do a bit of reading and enable lazy init even if it defaults to off. Thank you, --Ed