Question regarding correct linux cdrecord device and buffer issues.
Hello.
I have some questions about dvd burning with cdrecord.
1)
The device choice was always a gray area in linux but in older times
it was more clear. With 2.4 linux kernel there was ide-scsi support.
With early 2.6 there was dev=ATAPI:x,y,z.
Nowadays with recent kernels (for example 2.6.28) i can use two namings.
The /dev/sr0 and the usual x,y,z naming.
I tried to read the archives and came to believe that using dev=x,y,z is
better than dev=/dev/sr0. Is that correct ?
2) There are some things about the buffer in the cdrecord output that i
don't understand. The command i use is "cdrecord -v -dao file_to_write"
and the output is the following.
Cdrecord-ProDVD-ProBD-Clone 2.01.01a53 (i686-pc-linux-gnu) Copyright
(C) 1995-2008 J�rg Schilling TOC Type: 1 = CD-ROM
scsidev: '/dev/dvdrw'
devname: '/dev/dvdrw'
scsibus: -2 target: -2 lun: -2
Warning: Open by 'devname' is unintentional and not supported.
Linux sg driver version: 3.5.27
Using libscg version 'schily-0.9'.
Driveropts: 'burnfree'
SCSI buffer size: 129024
atapi: 1
Device type : Removable CD-ROM
Version : 5
Response Format: 2
Capabilities :
Vendor_info : 'TSSTcorp'
Identifikation : 'CDDVDW SH-S223Q '
Revision : 'SB02'
Device seems to be: Generic mmc2 DVD-R/DVD-RW/DVD-RAM.
Current: DVD+R
Profile: DVD-R/DL sequential recording
Profile: DVD-R/DL layer jump recording
Profile: DVD-RW/DL
Profile: DVD+R/DL
Profile: DVD+R (current)
Profile: DVD+RW
Profile: DVD-RW sequential recording
Profile: DVD-RW restricted overwrite
Profile: DVD-RAM
Profile: DVD-R sequential recording
Profile: DVD-ROM
Profile: CD-RW
Profile: CD-R
Profile: CD-ROM
Profile: Removable Disk
Using generic SCSI-3/mmc-3 DVD+R driver (mmc_dvdplusr).
Driver flags : NO-CD DVD MMC-3 SWABAUDIO BURNFREE
Supported modes: PACKET SAO LAYER_JUMP
Drive buf size : 1409024 = 1376 KB
FIFO size : 33554432 = 32768 KB
Track 01: data 4343 MB
Total size: 4343 MB = 2223942 sectors
Current Secsize: 2048
Blocks total: 2295104 Blocks current: 2295104 Blocks remaining: 71162
Reducing transfer size from 129024 to 98304 bytes.
Starting to write CD/DVD/BD at speed 22 in real SAO mode for single
session. Last chance to quit, starting real write 0 seconds.
Operation starts. Waiting for reader process to fill input buffer ...
input buffer ready. Starting new track at sector: 0
Track 01: 4343 of 4343 MB written (fifo 100%) [buf 99%] 22.4x.
Track 01: Total bytes read/written: 4554633216/4554633216 (2223942
sectors). Writing time: 245.045s
Average write speed 13.4x.
Min drive buffer fill was 98%
Fixating...
Fixating time: 36.096s
BURN-Free was 20 times used.
cdrecord: fifo had 46333 puts and 46333 gets.
cdrecord: fifo was 0 times empty and 6481 times full, min fill was 43%.
The following is from another burn.
Writing time: 254.371s
Average write speed 13.2x.
Min drive buffer fill was 98%
Fixating...
Fixating time: 38.083s
BURN-Free was 22 times used.
cdrecord: fifo had 47449 puts and 47449 gets.
cdrecord: fifo was 0 times empty and 7882 times full, min fill was 95%.
2a)
The question i have is why BURN-Free was used when the buffer wasn't
empty ? In one time it is 43% and in the other time 95%
Isn't burnfree used when the buffer is empty ?
2b)
The above results are from burning YUDEN003 16x DVD+R at default
speed which is 22x for this media. I notice that until 20x everything
works fine. When the speed tries to get 22 it continuously goes
20-21-20-21 etc like it can't keep up with the speed. Is burnfree being
activated due to this ?
If yes how can i correct it ? Ofcourse i don't care about the 10secs
i will gain from the 20 -> 22x change but i just want everything to work
correctly in my system. I am fairly sure my hard disk's speed isn't the
problem.
2c) It is reducing the transfer size from 129024 to 98304 bytes.
I read in the a54 changelog that the transfer size was reverted to 63kb
because the kernel can't handle it. Is this the same thing ?
Does this reducing to 98304 cause any problems ?
cdrecord -scanbus output is the following:
Cdrecord-ProDVD-ProBD-Clone 2.01.01a53 (i686-pc-linux-gnu) Copyright
(C) 1995-2008 Jörg Schilling Using libscg version 'schily-0.9'.
scsibus2:
2,0,0 200) 'TSSTcorp' 'CDDVDW SH-S223Q ' 'SB02' Removable
CD-ROM
2,1,0 201) *
2,2,0 202) *
2,3,0 203) *
2,4,0 204) *
2,5,0 205) *
2,6,0 206) *
2,7,0 207) *
/etc/default/cdrecord is the following:
#ident @(#)cdrecord.dfl 1.4 02/07/07 Copyr 1998 J. Schilling
CDR_DEVICE=samsung
CDR_FIFOSIZE=16m
# drive name device speed fifosize driveropts
samsung= /dev/dvdrw -1 32m burnfree
My distro is slackware 12.2 and i use the genuine cdrtools
suite and not any fork. I will gladly provide any more info
you need.
I am sorry for the long post and thank you for your time.
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