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?

> 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.

Cheers,

--Ian
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