4 DVD-RW Drives, Can I Burn 3 DVD's At Once?

[Ponch]

Also note that even if the drive is told to burn at 16X that is the maximum rate which only occurs when on the outer cylinder

Noticed they talk "rpm" only for HDDs and not for optical drives ? CDs & DVDs rotate at various speed, keeping the linear speed constant. There is no faster part on a DVD. "16x" is a constant write or read speed.

[DigeratiPrime]

I am not so sure, maybe if the disc is written using the CLV (Constant Linear Velocity) method.

With CAV, P-CAV, and Z-CAV I've noticed the speeds accelerate using ImgBurn.

http://club.cdfreaks.com/f61/p-cav-cav-z-cav-clv-etc-94541/

http://www.cdspeed2000.com/faq.html#4

I think if you did a 16X CLV the disc might shatter or write a ton or errors, but I don't know if 16X DVD = 16X CD in terms of velocity.

[Ponch]

Sorry then, I'm obviously wrong for the writing part (which was the point here).

[DigeratiPrime]

Hey no problem I actually posted that I was wrong originally because what you said made sense, I then remembered that bit and had to edit my post

BTW the Mythbusters did try the shatter myth in their second episode

http://www.youtube.com/watch?v=v0QT4Y1Y3ug

This guy is saying DVD's can go up to 32,000 RPM which I calculate to be approx 56X on the high end and 20X on the low.

http://hypertextbook.com/facts/2003/ClerbieMontilus.shtml

I recommend burning dvds at 8X anyway to get better burn quality

http://club.cdfreaks.com/f33/slow-write-sp...no-good-247643/

Also the mode the drive uses is determine by the drives controller, and not by software

http://forum.doom9.org/showthread.php?t=128732

[GrofLuigi]

I recommend burning dvds at 8X anyway to get better burn quality

http://club.cdfreaks.com/f33/slow-write-sp...no-good-247643/

I have a problem with that thread. Although he seems to go 'myth busting' he gives no actual evidence except 'that and that speed is better supported by the drive/media'.

What does supported mean? In which way one is supported better than another?

I agree with what he wrote that there is much misinformation and word of mouth about this carried over from the old times (times of CD writing). But CD/DVD writing (I'm not talking about anything higher, i.e. BluRay, as I have no experience with that) has been an evolution - over time only the choice of materials and speeds changed, everything else is pretty much the same. And we still live in the same universe where the laws of physics haven't changed (more speed = more jitter). And I haven't heard of any claims by the manufacturers of 'new technology' - that would be major selling point for them, worth at least a press release.

So I cannot imagine how in the world any higher speed can be better than any lower speed (under ANY circumstances). If it is true, it can be only due to bad/unoptimized write strategy of the burner.

GL

*Edit: That thread isn't so bad after all. All I had to do was turn a page.

Edited April 19, 2009 by GrofLuigi

[jcarle]

jcarle what is the read benchmark on your raid 0 unit and what controller does it use?

It's the Intel ICH10R RAID. I can hit the 150MB+ range in my read but the problem is not with sequential read, it's with random I/O. The random I/O for simultaneously feeding data to a burner grows significantly for each burner added.

[DigeratiPrime]

The only way to get around the random IO limitation is to get the minimum throughput up or use a SSD or RAM drive.

[DigeratiPrime]

More ideas:

• First make sure the image files are defragmented on the hard drive.
  
• Or read the images off separate USB drives - USB 2.0 can do 60MB/s.
  
• Stop programs, services, and disable the network interface - to reduce IO usage.
  
• Then maybe increase the IO Buffer Size; the default is 40MB and the maximum is 512MB.
  
• Might want to do some tests with DVD-RW media first.