On Mon, Nov 24, 2003 at 10:23:12AM +0100, Paul Bijnens wrote:
> 
> Read on a few lines further in the man page.  The most important
> parameter for speed is the estimated size.  It's the stop/start when
> writing a filemark that slows down the most.  The default estimated
> size is 1 Gbyte.  Amtapetype will write 100+200 files to the tape only
> if the estimated size is more or less ok.  If you insert a a tape
> with 200 Gbyte real capacity, amtapetype will actually write 20000+60000
> files to the tape.  If start/stop takes about a second, then there
> will be 80000 seconds lost in writing filemarks only, instead of
> the expected 300 seconds.


Might it be a good idea to have amtapetype note too many files
being written during the first phase and taking some action?
Maybe with an option to override the checking.

Possible actions:

 - abort with an error message to rerun with a different estimate
   when the number of files written exceeded some value, say 250

 - print an error message recommending the operator interupt the
   and rerun with a corrected estimate, eg.

amtapetype: pass 1: estimated tape capacity (X GB) error: expected
to write 100 files, now writing file Y00: restart recommended

   In your example above (200GB tape with default estimate) I
   think the error message would come out about every minute or
   two.  For a dds3 tape, about every 20 min.

Aside from the new option processing to set an "override flag)
I think all it would take is an if statement like:

   if (files_written % 100 && files_written > 100 && ! overried_flag)
   {
        print/log errors
   }

jl
-- 
Jon H. LaBadie                  jon AT jgcomp DOT com
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