sg in 2.4.18

sg in 2.4.18

[William Thompson]

Is it possible to open sg more than once for multiple devices?

IE, cdrecord 2 cds at once.

Re: sg in 2.4.18

[William Thompson]

> > Is it possible to open sg more than once for multiple devices?
> > IE, cdrecord 2 cds at once.
> 
> Each cd writer will have its own /dev/sg* device so yes

Thanks, I was wondering as I remember that having one open would block
another.  I last tried it on a 2.2.13 kernel when trying to read 2 audio
discs which didn't work.

Re: sg in 2.4.18

[Alan Cox]

> Is it possible to open sg more than once for multiple devices?
> IE, cdrecord 2 cds at once.

Each cd writer will have its own /dev/sg* device so yes

Re: sg in 2.4.18

[Richard B. Johnson]

On Mon, 13 May 2002, William Thompson wrote:

> Is it possible to open sg more than once for multiple devices?
> 
> IE, cdrecord 2 cds at once.
> -

Yes, but not the same device. Each CD should have its own device.
FYI, it works very well with SCSI devices, but I haven't tried
it with IDE.


Cheers,
Dick Johnson

Penguin : Linux version 2.4.18 on an i686 machine (797.90 BogoMips).

                 Windows-2000/Professional isn't.

Re: sg in 2.4.18

[Justin Piszcz]

I have two Plextor 12/10/32A CDRW's.

IDE 0 - MASTER: HDD
             SLAVE: Plextor
IDE 1 - MASTER: Plextor

I burn two cds at the same time at 12X.

The catch is, the Plextors have burn proof.

When the CD-R drive goes to finalize the disc on IDE 0, the IDE 1 stops
writing for 3-5 seconds, then it continues.

This is because it is on the same chain as the HDD.

So you ask, why not get a Promise controller and do that?
I also have an ATA 100 Promise controller.

Believe it or not, any combination with the promise controller only yields
results worse than the setup I've mentioned above.

I'm not sure why, but any combination you can think of (between the card, and

two IDE busses on the motherboard) I have tried.

Any combination involving the promise makes each drive resort to burnproof
every 5-10 seconds, when I was doing tests, it took about 30-40 minutes to
burn @ 12X (two cds parellel) due to falling back to burnproof every 5
seconds or so.

Also, putting both burners on the same chain currently does not work.
Because when cdrecord sends the command to FIX the cd after it is done
burning the data, the command gets sent to both IDE drives causing cdrecord
to blow up (the burn fails) on the other burner.



William Thompson wrote:

> Is it possible to open sg more than once for multiple devices?
>
> IE, cdrecord 2 cds at once.
> -
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Re: sg in 2.4.18

[Mike Fedyk]

On Mon, May 13, 2002 at 11:41:30AM -0400, Justin Piszcz wrote:
> I have two Plextor 12/10/32A CDRW's.
> 
> IDE 0 - MASTER: HDD
>              SLAVE: Plextor
> IDE 1 - MASTER: Plextor
> 
> I burn two cds at the same time at 12X.
>

I have a yamaha 16x and a nec 24x, both are IDE.

[snip]
> Believe it or not, any combination with the promise controller only yields
> results worse than the setup I've mentioned above.
> 
> I'm not sure why, but any combination you can think of (between the card, and
> 
> two IDE busses on the motherboard) I have tried.
> 
> Any combination involving the promise makes each drive resort to burnproof
> every 5-10 seconds, when I was doing tests, it took about 30-40 minutes to
> burn @ 12X (two cds parellel) due to falling back to burnproof every 5
> seconds or so.
>

Strange, can you read through the thread "A CD with errors (scratches etc.)
blocks the whole system while reading" and see if you are having a similar
problem?

> Also, putting both burners on the same chain currently does not work.
> Because when cdrecord sends the command to FIX the cd after it is done
> burning the data, the command gets sent to both IDE drives causing cdrecord
> to blow up (the burn fails) on the other burner.

Hmm, I wonder in Andre can say anyting about this.

What kernel version are you running?

Can you post the output of lspci?

With both drives running at the same time, each on a seperate cable and
controller, I was able to write without trouble.

00:00.0 Host bridge: Intel Corp. 440FX - 82441FX PMC [Natoma] (rev 02)
00:07.0 ISA bridge: Intel Corp. 82371SB PIIX3 ISA [Natoma/Triton II] (rev 01)
00:07.1 IDE interface: Intel Corp. 82371SB PIIX3 IDE [Natoma/Triton II]
00:07.2 USB Controller: Intel Corp. 82371SB PIIX3 USB [Natoma/Triton II]
(rev 01)
00:08.0 VGA compatible controller: Trident Microsystems TGUI 9660/968x/968x
(rev d3)
00:09.0 Unknown mass storage controller: Promise Technology, Inc. 20262 (rev
01)
00:0a.0 Ethernet controller: Intel Corp. 82557 [Ethernet Pro 100] (rev 02)
00:0b.0 SCSI storage controller: Adaptec AHA-7850 (rev 03)

Re: sg in 2.4.18

[Andre Hedrick]

On Thu, 16 May 2002, Mike Fedyk wrote:

> On Mon, May 13, 2002 at 11:41:30AM -0400, Justin Piszcz wrote:
> > Also, putting both burners on the same chain currently does not work.
> > Because when cdrecord sends the command to FIX the cd after it is done
> > burning the data, the command gets sent to both IDE drives causing cdrecord
> > to blow up (the burn fails) on the other burner.
> 
> Hmm, I wonder in Andre can say anyting about this.

The short answer is the driver currently does not support proper overlap
and release of the bus (channel/hwif).  Until this is committed to code to
support a multi-threaded request to schedule on service priorities, it is
not doable.  Burn-Proof will greatly assist in a solution, as a means to
force the device to spin while doing dual burns.  Thus some means for a
channel/hwif merging queue is needed.  I have a partial whiteboard
solution but it is incomplete.

> What kernel version are you running?
> 
> Can you post the output of lspci?
> 
> With both drives running at the same time, each on a seperate cable and
> controller, I was able to write without trouble.
> 
> 00:00.0 Host bridge: Intel Corp. 440FX - 82441FX PMC [Natoma] (rev 02)
> 00:07.0 ISA bridge: Intel Corp. 82371SB PIIX3 ISA [Natoma/Triton II] (rev 01)
> 00:07.1 IDE interface: Intel Corp. 82371SB PIIX3 IDE [Natoma/Triton II]
> 00:07.2 USB Controller: Intel Corp. 82371SB PIIX3 USB [Natoma/Triton II]
> (rev 01)
> 00:08.0 VGA compatible controller: Trident Microsystems TGUI 9660/968x/968x
> (rev d3)
> 00:09.0 Unknown mass storage controller: Promise Technology, Inc. 20262 (rev
> 01)
> 00:0a.0 Ethernet controller: Intel Corp. 82557 [Ethernet Pro 100] (rev 02)
> 00:0b.0 SCSI storage controller: Adaptec AHA-7850 (rev 03)
> 

Andre Hedrick
LAD Storage Consulting Group