[PLUG] DVD+-WTF

[Jeme A Brelin]

OK, I'm having data throughput problems.  I don't think I should, but 
maybe somebody knows better.  The motherboard is some Tyan Tiger model 
(don't recall which at the moment).  Dual Athlon MP 1.8GHz (whatever 
number designation that is).  1GB RAM.  No swap.

/dev/hdb -- 120GB IDE drive
jbrelin at person:~/school$ hdparm /dev/hdb

/dev/hdb:
  multcount    =  0 (off)
  IO_support   =  1 (32-bit)
  unmaskirq    =  1 (on)
  using_dma    =  1 (on)
  keepsettings =  0 (off)
  readonly     =  0 (off)
  readahead    = 256 (on)
  geometry     = 65535/16/63, sectors = 240121728, start = 0


/dev/hdc -- DVD+-RW drive
jbrelin at person:~/school$ hdparm /dev/hdc

/dev/hdc:
  IO_support   =  0 (default 16-bit)
  unmaskirq    =  0 (off)
  using_dma    =  1 (on)
  keepsettings =  0 (off)
  readonly     =  0 (off)
  readahead    = 256 (on)
  HDIO_GETGEO failed: Invalid argument

/dev/hdd -- DVD-ROM
/dev/hdd:
  IO_support   =  1 (32-bit)
  unmaskirq    =  1 (on)
  using_dma    =  1 (on)
  keepsettings =  0 (off)
  readonly     =  0 (off)
  readahead    = 256 (on)
  HDIO_GETGEO failed: Invalid argument

/dev/sda -- 20 GB SCSI HD


OK, so I'm trying to write some DVDs.

Created an ISO in a fairly normal way (may as well be a big pile of 
zeroes, though).  Using growisofs to burn with
growisofs -Z /dev/hdc=file.iso

It chugs along for a while (varies wildly) and then the write speed drops 
to 0.0 for a while and the failure pops up.

Seems to me like some buffer is emptying, but you'd think if I shut 
everything else down and ran the thing from tty1, it'd do better.  It 
doesn't.

The few times it's appeared to work, the disks had some files that 
consistently could not be read from any drive (though most of the data can 
be read from any drive I tried).

What the hell am I missing?

J.
-- 
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      Jeme A Brelin
     jeme at brelin.net
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