[Pkg-libburnia-devel] Bug#567056: brasero: Brasero is very slow burning a data DVD-R

[Thomas Schmitt]

Hi,

Leandro Lucarella:
> > > Burning some files in a data DVD using brasero is very slow. I get 2.6x
> > > speed at most and my drive is 8x capable. Using growisofs directly,
> > > i get a 6.6x speed average (which seems reasonable for a 8x drive).
Josselin Mouette:
> > My guess goes for a bug in libburn; one specific to the drive, since I
> > haven't noticed such a slowdown with my 16x burner.
George Danchev:
> Thomas, do you have any rough idea what might be the cause for such low
> rates to be picked as compared to growisofs?

We had a hunt for speed in November.
One of my USB drives was slower with libburn
than with growisofs. Users had similar problems.

The reason is not really clear. External drives
changed their speed when being plugged into
another computer. eSATA was faster than USB with
the same drive and computer.
growisofs did not always outperform libburn.

With some drives speed got improved by using
libburn ./configure options
  --enable-dvd-obs-64k
or
  --enable-track-src-odirect
and then
  make clean ; make

Without compiling, one may also use cdrskin or
xorriso for experiments.
  cdrskin ... dvd_obs=64k ...
  xorriso ... -dvd_obs 64k ...

Inside Brasero one could use for testing:
  void burn_write_opts_set_dvd_obs(struct burn_write_opts *opts, int obs);
with obs = 65536 .
The call is available since libburn-0.7.4
(december 2009).


> product: LITE-ON DVDRW SOHW-832S
> logical name: /dev/hda

Are there any indications that DMA might not
really be in effect ?
(Hopping cursor, high CPU load with "WAIT".)

Do you get better throughput if running the
program as superuser ?


Have a nice day :)

Thomas