On Thu, 11 Mar 2004 at 2:21pm, Jonathan Dill wrote

> I would try "amrestore -c" to just dump the image off the tape, and then 
> do the uncompress and extraction separately, but you will need enough 
> disk space to do it.  Worst case, you could try "amrestore -r" and use 
> "dd bs=32k skip=1 if=dump-file" to skip over the header, and then pipe 
> that to the uncompress and extract processes.

The current slow-running process is 'amrestore -r'.  I'm guessing it's 
forcing the block size that's the culprit here -- the amrestore man page 
isn't quite clear, but it seems to say that if you don't specify -b, 
it'll default to 32k.  I tried just 'dd if=/dev/nst1 of=img.raw' but it 
said "dd: reading `/dev/nst1': Cannot allocate memory".  tapeinfo says 
this about blocksizes for the drive:

MinBlock:2
MaxBlock:16777215

Maybe I should try dd with bs=16M?  But will that pad the output file with 
an unacceptable-to-tar chunk at the end since the tapefile is unlikely to 
be an exact multiple of 16M?

Thanks.

-- 
Joshua Baker-LePain
Department of Biomedical Engineering
Duke University