On Thu, 23 Aug 2007, CyberLeo Kitsana wrote: > Ian Smith wrote: > > My knowledge of this is thin, despite reading McKusick's paper through > > several times, but we're told that background fsck runs on a snapshot of > > the fs concerned. How any bg fsck corrections are woven back into the > > live fs later is still a mystery to me, but that's because I still have > > an only barely superficial understanding of how snapshots work .. > > Background FSCK only repairs a small subset of filesystem > incosistencies. Specifically, those inconsistencies that softupdates > allows to occur, such as data blocks allocated out of the bitmap, but > not actually assigned to any inode. Background FSCK only needs to find > these (by looking at a fully consistent and unchanging snapshot of the > filesystem) and deallocate them in the live filesystem, a simple > operation given that it's guaranteed nothing will be using a block that > is both marked used and not assigned to anything.
Thanks for that nutshell, CL. Sometimes little bits help the most <&^}= _______________________________________________ freebsd-questions@freebsd.org mailing list http://lists.freebsd.org/mailman/listinfo/freebsd-questions To unsubscribe, send any mail to "[EMAIL PROTECTED]"
