[Pkg-opt-media-team] Bug#709971: dvd+rw-tools: growisofs more then 1 Bluray, since Debian 7 speed collapses

[Thomas Schmitt]

Hi,

this would be a blow for burn programs. I am maintaining libburn
and its applications cdrskin and xorriso. So i am interested in this
problem.

The main suspect would be the kernel in this case. The programs send
SCSI commands via ioctl(SG_IO) and wait until this ioctl call ends.
If they are slow, then the ioctl() is most probably to blame.


How are the drives attached to the computer ?
Internal SATA ? eSATA ? USB (between computer and SATA) ?
If USB: do SATA or eSATA work better ?

What performance do you get from reading multiple BD media via
the block device driver ?
E.g.
  time dd if=/dev/srX bs=65536 count=10000

What read performance do you get when reading via ioctl(SG_IO) ?
E.g.
  time xorriso -outdev /dev/srX \
               -check_media use=outdev min_lba=0 max_lba=320000 --

What happens if you let some of your drives read while others write ?

Probably it will not help to use a different burn program.
Nevertheless, if you want to try:
  xorriso -as cdrecord -v dev=/dev/srX filename.iso


You do not mention the known growisofs BD-R bug which causes
the message at the very end of the burn run:
  :-[ CLOSE SESSION failed with SK=5h/INVALID FIELD IN CDB]: Input/output error

If you are using BD-RE media, then try to write them via the block
device
  time dd if=filename.iso of=/dev/srX bs=65536


Have a nice day :)

Thomas