K3B not using buffers [solved]

[ianw1974]

I have Mandriva 2006 installed, and I've also noticed this problem in LE2005 as well. For some reason, K3B doesn't seem to be using the FIFO and Device buffers.

 

I know that when I used to use Nero in Windows, that it did buffer correctly, so unsure of whether this is just a feature of K3B, or whether I can change something to make it use the buffers.

 

I was trying to make a copy of one of my data DVD's, and it was copying at 1x instead of it's max speed of 8x. The maximum it fluctuated too was about 2x. This was using on-the-fly copying, although I wasn't sure whether it would be better copying to the hard disk as iso first, and then burning back later. Took about 45mins to burn the DVD on the fly. Windows only took 10 minutes.

[coverup]

I think the speed also depends on the media... I experienced a similar problem with cheap TDK DVD-Rs. Though they we rated 8x (or even 16x, can't remember), the actual speed was 2x using the 8x burner. The same burner burns 8x Verbatim DVD-Rs at 4x.

[AussieJohn]

Hello ianw.

As I understand it, when you do on the fly burning it does not use buffers anyhow.

 

I too have noticed that it does not show buffers when burning DVD data and not doing it on the fly such as burning ISOs. It doesn't ever give me any dvd drink coasters.

I have found that the burn speed seems to be determined very much by the data k3b reads about the blank disc before it starts the burn process. Could be just your discs so far as the speed is concerned.

I use TDK exclusively and can burn up to 16x but I usually select 8x, sometimes 4x, manually and k3b always seems happy with that.

 

Cheers. John.

[ianw1974]

Thanks guys. I'm currently using TDK DVD+R as I saw one of your (AussieJohn's) posts before about crappy cheap DVD's, and bought TDK based on your recommendation :P

 

It's funny, because if I burn copying data from the hard disk to the DVD it can be up to 8x no problems.

 

I did create one coaster by accident, I chose Copy CD and was doing 4.7GB DVD with it, and it failed of course :P

[scarecrow]

First, check if DMA is enabled for the burner (e.g. by hdparm -d /dev/hdc).

Second, the problem may be the DVDRW drive itself (firmware in use breaking MMC-3 compliancy due to "special features", like DVD-RAM burning or special vendor-specific burning features like LightScribe and such).

Can you post the exact drive model and firmware revision used?

Edited November 23, 2005 by scarecrow

[ianw1974]

I'll check the dma stuff later when I get home.

 

It's an LG DVDRW/DVD-RAM drive, 4061b I think, or something like that. I'd have to double check for sure when I get home, but this is what I vaguely remember.

 

As I say, Nero was fine, including using the TDK DVD's I have now :P

 

Hope the above helps a little.

[aRTee]

K3B cannot give buffer information since the backend for burning dvds is not cdrecord (or whatever the modern offspring of that is now called), but growisofs, which works differently.

Since all modern drives include buffer underrun protection (and it's in the spec for data dvd burning), there's nothing to worry about.

 

As for the burnspeed, it may be that the dvdrom and burner are on the same ide channel? Then they may not be able to pass data fast enough for 4x or 8x burning....?

[ianw1974]

They are sharing the same IDE channel, secondary :P

 

I'll probably burn to image first on hdd, and then up to DVD and see if this is any quicker. I believe it is from when I burnt something before, so I'll try again and see what happens.

 

Many thanks!