Out of necessity, we have some file systems that are 25 TB. As of 2009, we consider 25 TB a large file system and we are concerned about the potential downtime that may result if an fsck is needed.
Some storage vendors advertise that they can have single file systems that are hundreds of terabytes or even a petabyte. Often, however, there is no mention of when or if fsck or similar operations would be needed and how long they take.
ZFS claims to eliminate the need for fsck and Chunkfs (ext2 enhancements from around 2006) claims to reduce fsck times by splitting the repair domain. Further, “journaling file systems only speed fsck time in the case of a system crash, disconnected disk, or other interruptions in the middle of file system updates. They do not speed recovery in the case ‘real’ metadata corruption” (see third paragraph here).
1.) What do you consider a large file system? (What file system do you use for them?)
2.) Are you concerned about fsck times? (Why or why not?)
3.) Can you predict fsck times based on some parameters (e.g., inodes used, disk size, etc.)?
4.) Any special cases related to fsck or similar operations for clustered file systems?