Joshua,

Ah, I'd mistakenly, been under the impression that amanda might try
to write something smaller that would fit.

Since it doesn't attempt that, ever, there is no reason why it would
try to measure the space.

If it had done that there is a chance to put an upper bound on 
the size of the DLE - but I now understand that it is a non-issue.

Thanks for the explaination.

                                                Brian

On Mon, May 02, 2005 at 11:44:03AM -0400, Joshua Baker-LePain wrote:
> On Mon, 2 May 2005 at 11:24am, Brian Cuttler wrote
> 
> > silly question - if you hit EOT while trying to write a DLE to
> > tape... don't you know pretty closely how much room remains on
> > the end of the tape - at least to within one chunksize if not
> > something with smaller granularity ?
> 
> If you hit EOT, then by definition there's no room at the end of the tape.  
> If you mean "then we can rewind to the beginnning of this record and write 
> a DLE that we now know will fit", them amanda doesn't do that for the same 
> reason it doesn't append -- we don't trust tape drives enough to do 
> anything but write linearly.
> 
> In addition, your statement isn't necessarily true.  If you're using 
> hardware compression, then a different DLE will compress with a different 
> ratio, and may or may not fit in the number of blocks of the "failed" DLE.
> 
> -- 
> Joshua Baker-LePain
> Department of Biomedical Engineering
> Duke University
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