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View Full Version : What does the Ultra160 or 320 mean in SCSI driver ?



Cauchy
03-11-2004, 12:37 AM
What does the Ultra160 or 320 mean in SCSI driver ? Does it mean the rate of reads , Ultra160 is 160MB/s, and 320 is 320MB/s ? And which one I choose determes how many layers could I edit in VT real-time, right?

And I read the mannul of VT[2], it says:" For real-time, editingVT[2] needs 70MB/s(or faster) reads." And RTV file is about 22MB/s, so if I have a Ultra320 SCSI controler card and some Ultra320 SCSI drivers, I can edit about 320/22=10 layers RTV files, it is just a theory, regardless of the others factors like CPU and memory.


Do I think right?

robewil
03-11-2004, 09:50 AM
Yes, you think right as long as you keep in mind that it is in theory. Ultra 320 means the maximum throughput the interface can allow is 320 MB/sec with U 160 being half of that. Of course, you would need to have a very impressive RAID to come close to that 320 speed.

I believe some people are getting 10 realtime streams with their VT systems. That is probably near the current limit as some drive bandwidth is needed for audio and caching.

Jim Capillo
03-11-2004, 09:59 AM
I have (4) 73gb U320's in my RAID and I'm getting anywhere from 220 to 260 mbs (as reported by autoconfig). Can't say I've done 10 streams realtime, but 6 or 7 shouldn't be a problem.

For comparison, the IDE RAID - (4) 40gb - reports around 73-75 mbs.

Cauchy
03-11-2004, 08:27 PM
Originally posted by Jim Capillo
I have (4) 73gb U320's in my RAID and I'm getting anywhere from 220 to 260 mbs (as reported by autoconfig). Can't say I've done 10 streams realtime, but 6 or 7 shouldn't be a problem.

For comparison, the IDE RAID - (4) 40gb - reports around 73-75 mbs.


Could you tell me which CPU are you using for VT[3]? and what is autoconfig, a windows command or any soft?

My VT workstation is based on Duel Xeon 2.4, and 4 36GB Ultra 320 SCSI RAID. When I start to edit 5 layers of video clips, the playback is like "stopping smooth stop ....." Can it be called real-time editing? Is It equal to my hard system?

thank you!

Jim Capillo
03-11-2004, 08:48 PM
Originally posted by Cauchy
Could you tell me which CPU are you using for VT[3]? and what is autoconfig, a windows command or any soft?

My VT workstation is based on Duel Xeon 2.4, and 4 36GB Ultra 320 SCSI RAID. When I start to edit 5 layers of video clips, the playback is like "stopping smooth stop ....." Can it be called real-time editing? Is It equal to my hard system?

thank you!

I'm using a SuperMicro X5DA8 Dual 2.8 Xeon with 2 gigs of RAM.

Autoconfig is in the VT[3] folder on your installed drive and you should run it every time you install a new build or patch. It is a VT tool and basically, it detects your hardware and sets it to a benchmark. Most people change their settings as they experiment. If you are having trouble with certain parts of your timeline, you may want to adjust your settings or drop a force render under the problem area. This will cause the VT to render the problem area before playback gets to it, thereby smoothing everything out.

Paul Lara
03-12-2004, 07:06 AM
Originally posted by robewil
I believe some people are getting 10 realtime streams with their VT systems. That is probably near the current limit as some drive bandwidth is needed for audio and caching.

Actually, a 64-bit PCI bus will max out at about 7 streams of video. However, smokin' fast U320 drives can background cache those other three clips faster than you can build 'em, making it seem as if it's real-time!

To see what the hard limit of your system is, you can go into Prefs and turn off background rendering.

SBowie
03-12-2004, 10:29 AM
Originally posted by Paul Lara
To see what the hard limit of your system is, you can go into Prefs and turn off background rendering. You are supposing I ever had it turned it on .... ;)