Bug#567056: brasero: Brasero is very slow burning a data DVD-R

[Thomas Schmitt]

Hi,

for some reason i did not get the last two
mails from Leandro.
Only good that George brought me back to the
topic.


I propose to next explore libisofs without a
burn process being involved.
If Brasero can burn to a disk file as "drive"
target, then try whether it is as slow as with
optical media.

Another test would be to install xorriso.
E.g. by
  apt-get source libisoburn

or from source
  http://scdbackup.sourceforge.net/xorriso-0.4.8.pl01.tar.gz
build by: 
 tar xzf ..../xorriso-0.4.8.pl01.tar.gz
 cd xorriso-0.4.8
 ./configure
 make
 make install (or execute as ./xorriso/xorriso)

One my run it by its mkisofs emulation

  xorriso -as mkisofs -o /dev/null \
          -R -J \
          file_or_dir_1 file_or_dir_2 ... 

which will tell no speed numbers.
Or by its own CLI 

  xorriso -outdev stdio:/dev/null \
          -add file_or_dir_1 file_or_dir_2 ...

which will give a progress report with DVD speed
measurements
  xorriso : UPDATE : Writing:    3257s    0.5%   fifo   0%  buf  50%
  xorriso : UPDATE : Writing:   20875s    3.0%   fifo   0%  buf  50%   62.7xD 
  ...
  xorriso : UPDATE : Writing:  664063s   96.8%   fifo   0%  buf  50%   56.4xD 
  ISO image produced: 685604 sectors

This is on a 3000 MHz AMD. About 20 times faster
than you experience with Brasero.

If this works fast, then you should try a
dummy run with DVD-R:

  xorriso -outdev /dev/sr0 -dummy on \
          -add file_or_dir_1 file_or_dir_2 ...


If any of the xorriso tests is slow, then i will
have to invent a theory and some experiments to
verify it.
(Any hint is welcome then.)

If they all are fast, then one will have to
search the bottleneck in Brasero.


Have a nice day :)

Thomas