On Aug 18, 2009 13:03 -0400, Theodore Ts'o wrote: > Something we *could* do to further reduce the chances would be to > compare the primary and backup group descriptors, either at > mount-time, or in e2fsck. This would add an extra level of paranoia, > although the people who are trying to do 5 second boots with HDD's > would probably complain about the extra seeks that we'd be introducing > as a result. I've thought about this recently as well. Since the GDT blocks are allocated contiguously (at least until we get META_BG filesystems) it would only be a single extra seek and read at mount time. For a 16TB filesystem there are 8MB of GDT blocks, so that isn't a huge amount of extra IO as log as we do it with a single read instead of many seeks. Cheers, Andreas -- Andreas Dilger Sr. Staff Engineer, Lustre Group Sun Microsystems of Canada, Inc. -- To unsubscribe from this list: send the line "unsubscribe linux-ext4" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
