what is cdrecord doing?

[Michael Hennebry]

I used cdrecord to burn a DVD.
It seems to have worked, but the output confuses me.
The last line is:
Track 01: Total bytes read/written: 399360/614400 (300 sectors).

When I've done CD's the read/written
numbers were usually exactly the same.
They were never that different.
What is going on?   Why the big difference?

I'm running FC5.
The entire output follows, there is some wraparound:
[root at 24-116-184-47 hennebry]# cdrecord -dao -dev=ATA:1,1,0 display.iso
Cdrecord-Clone 2.01.01a03-dvd (i686-pc-linux-gnu) Copyright (C) 1995-2005
Jörg Schilling
NOTE: This version contains the OSS DVD extensions for cdrtools and thus
may
      have bugs related to DVD issues that are not present in the original
      cdrtools. Please send bug reports or support requests to
      http://bugzilla.redhat.com/bugzilla The original cdrtools author
should
      not be bothered with problems in this version.
scsidev: 'ATA:1,1,0'
devname: 'ATA'
scsibus: 1 target: 1 lun: 0
Linux sg driver version: 3.5.27
Using libscg version 'schily-0.8'.
cdrecord: Warning: using inofficial libscg transport code version (schily
- Red Hat-scsi-linux-sg.c-1.85-RH '@(#)scsi-linux-sg.c        1.85
05/05/16 Copyright 1997 J. Schilling').
Device type    : Removable CD-ROM
Version        : 0
Response Format: 2
Capabilities   :
Vendor_info    : 'TOSHIBA '
Identifikation : 'DVD-ROM SD-R5112'
Revision       : '1031'
Device seems to be: Generic mmc2 DVD-R/DVD-RW.
cdrecord: Found DVD media: using cdr_mdvd.
Using Session At Once (SAO) for DVD mode.
Using Session At Once (SAO) for DVD mode.
Using Session At Once (SAO) for DVD mode.
Using generic SCSI-3/mmc DVD-R(W) driver (mmc_mdvd).
Driver flags   : SWABAUDIO BURNFREE
Supported modes: PACKET SAO
scsi_set_streaming
Speed set to 2822 KB/s
Starting to write CD/DVD at speed   2.0 in real SAO mode for single
session.
Last chance to quit, starting real write    0 seconds. Operation starts.
trackno=0
cdrecord: WARNING: Drive returns wrong startsec (0) using -150
Track 01: Total bytes read/written: 399360/614400 (300 sectors).
[root at 24-116-184-47 hennebry]#
:end of entire output

-- 
Mike   hennebry at web.cs.ndsu.NoDak.edu
"it stands to reason that they weren't always called the ancients."
                                                      --  Daniel Jackson