Hi,

I'm trying to use DVD-Ram under Suse 10.1 and set it up as follows:

mkudffs --media-type=dvdram /dev/dvdram

fstab:
/dev/dvdram /media/dvdram udf noatime,rw,noauto,users,exec,gid=users,utf8 0 0

It works, but if I want to copy a bigger file, let's say 1.5 GB, then after writing 256 GB the dvd-drive stops rotating and the hard-disk starts to be working heavily (load 4.9). This goes on for at least 7 minutes. After that time I begin to have mercy with my disk and switch off the computer (I tried to kill the corresponding processes with kill -9 ..., but it didn't work).

I also tried to set up packet writing with
pktsetup /dev/dvdram /dev/hda
but it didn't work. The error message is:
ioctl: Invalid argument

The node dvdram already exists. If I use it with a nonexisting node like
pktsetup /dev/pktdvd0 /dev/hda
it displays
ioctl: Inappropriate ioctl for device

Does anybody know how I can cure this or why this happens?
My notebook is rather new and has 1 GB RAM and Core Duo.

Best,
Mat

P.S.: Smaller files work without any trouble.

DVD RAM is great for small files. It not so good at very large files.
Plus the longer time you spend writing the more you put yourself at the mercy of the hardware.

Split the file using an archiver.

Interesting choice in file transfer though. I was under the impression usb thumbnail drives were all the rave. And better too.

Hi,

what does "great for small files" mean? Does it mean one has for a long period of time heavy access to the hard-disk, if one copies big files (as in my case)?

I don't see why it should be like that also for big files, since if you burn a big file on a DVD+RW you don't have that access either. It looks like heavy swapping, but why should it do that? I don't have that little RAM.

And what could be the cause for the error message for the packet writing software?

Because with the dvd-ram format files are copied to memory before being copied to the dvd, to ensure reliable transfer. Something particularly important for incremental writing i guess.

I could be wrong, but whats your swap usage when you try to copy over 1 gigabyte files?

what does your system monitor say?

Hi,

thanks for your help. This could be the case. Before I try it out and check my free memory: do you know what I have to kill to stop the swapping? I don't always want to switch off the computer. That's probably not very good for the data consistency (I have xfs). Killing the cp-command doesn't help. As well as unmounting the DVD-Ram with option -f.

In order to prevent this behaviour: is it possible to burn to a DVD-Ram with the usual methods (TAO or DAO)? I tried to burn with k3b, but it refuses to burn to DVD-Ram.

Oh, and what archiver would you suggest to split up a file? Especially can I put the files togther again under windows? I would like to do some file transfer between the operating sytems.

Thanks,
Mat

Hi,

I tried now to copy small files to DVD-Ram, that have 338M in total, but the same problem occurs. After some time the hard-disk is accessed, with seemingly no end. I also installed the packet-writing software with
The corresponding line in fstab is
It works, but it doesn't cure the problem. It seems DVD-Ram under Linux is completely useless for me.
I also figured out, that the hard-disk access is not for swapping. Only the normal hard-disk is accessed. Maybe for comparison of the created files (since DVD-Ram performs such a comparison)? But why does that take ages? It shouldn't I guess. B.t.w., never saw it terminating.

Best,
Matthaeus