Softupdates

In computer file systems, softupdates are an approach to maintaining disk integrity after a crash or power outage. They are an alternative to journaling file systems.

Instead of duplicating metadata writes in a journal, softupdates work by properly ordering the metadata writes to guarantee consistency after a crash. Like journaling, softupdates do not guarantee no lost data, but do make sure the filesystem is consistent.

Softupdates were first introduced to FreeBSD by Marshall Kirk McKusick and are now available across the BSDs.