[lkml]   [1999]   [May]   [31]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
Messages in this thread
    SubjectRe: XFS and journalling filesystems

    On Fri, 28 May 1999 10:11:02 -0600, "Jeff Merkey"
    <> said:

    > NTFS, for example, only posts meta data to the log file for restart,
    > and does not post user writes to the journal. This means you can
    > lose user data on a restart.

    This is expected behaviour. This is the defined Unix semantics. Unix
    provides an API which allows the application to request data
    synchronisation with the disk if it wants it --- the semantics
    explicitly do not guarantee this unless you use fsync/fdatasync or

    > If XFS is only writing meta data to the journal, and not user data,
    > as you suggest, then you are technically correct that reads do not
    > have to be serialized, however, this also means that XFS is not a
    > **TRUE** journalling file system because you can lose user data on
    > restarts

    Of course it is true journaling. It just has different semantics to a
    system which journals data synchronously.

    > and the benefits it provides for journalling are not much better
    > than running "fsck" after a system crash.

    That is the whole point, tho. fsck elimination is precisely why most
    Unix journaling filesystems were written.

    > Surely this is not the case -- this would mean that XFS is no better than
    > NTFS.



    To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
    the body of a message to
    Please read the FAQ at

     \ /
      Last update: 2005-03-22 13:52    [W:0.021 / U:0.480 seconds]
    ©2003-2016 Jasper Spaans. hosted at Digital OceanAdvertise on this site