On Tue, Sep 05, 2006 at 12:23:08PM -0400, Ian Turner wrote: | On Tuesday 05 September 2006 05:21, Phil Howard wrote: | > On Mon, Sep 04, 2006 at 11:01:20PM -0400, Ian Turner wrote: | > | On Saturday 02 September 2006 16:21, Phil Howard wrote: | > | > It would not need to be separate for each OS. The idea of using a | > | > partition table isn't even the only approach. | > | > If all that is written is tar format, nothing more needs to be added. | | Ah, but if you ditch the partition table, then indeed more needs to be added. | How else would you tell the end of one dump from the start of the next?
That would indeed be a limitation. Using partitions would be better. Not doing so could still be an option for those that know they have no need to do more than one dump per media. | > I didn't keep any stats, or really do it scientifically. Someone that | > wants to should probably control for a lot of the variables that influence | > it. But I do recall the speed improvement is about 25% to 30%. I suspect | > much of that is OS work bypassed with O_DIRECT. | | I suspect you incur a substantial performance penalty if other processes are | using the disk concurrently, because then you only get one write() per | elevator traversal. The disk being used for backup would have to be dedicated. You could get away with doing it all entirely inside one partition of a non-dedicated disk. But I'm focused on the backups that go to external media, which can be a real tape, if tape were a viable option, or to an external SATA disk in a separate disk enclosure, plugged in as needed. -- ----------------------------------------------------------------------------- | Phil Howard KA9WGN | http://linuxhomepage.com/ http://ham.org/ | | (first name) at ipal.net | http://phil.ipal.org/ http://ka9wgn.ham.org/ | -----------------------------------------------------------------------------
