RAW video in Vegas Pro 12

[Dave Haynie]

I’m not talking about peak streaming performance here. Yeah, you can do 220MB/s reads on your RAID.. but only in large chunks from a single file. Try running a multithreaded benchmark like CrystalDiskMark on your RAID, just for grins.

The math is simple.. let’s say you have a 10ms average seek time, 60MB buffers, and four files. So, you reason, you have a 220MB/s system, you ought to be able to fill all four buffers every second… 250ms per load. Only, with that seek, it really takes 260ms.. so you finish in 1040ms. Ok, not too bad.

How about this time we buffer up 44 things at 5MB each. So those ought to read, ideally, in 22.72ms each. But with the seek, that’s now 32.72ms each… so it takes 1.44 seconds per block… nearly 50% more time. Only, that’s kind of cheating, because there’s a bunch of additional overhead as you go to smaller blocks. Running ATTO Disck benchmark, I see single reads of 5MB blocks at only 143MB/s on my RAID, versus 325MB/s for a 64MB read or 365MB/s for an 8GB read. De-rating for block size, now that thing that ought to take 1 second actually takes 3.3 seconds.

And of course, that’s ignoring a bunch of overhead, and you don’t know exactly how Vegas is reading things: how many, what block size, seeks, etc. A taste of reality… I ran CrystalDiskMark on that same drive; it reported 244.8MB/s for the reads based on sequential reads of 1MB each (more overhead than 64MB or 8GB single reads). Going to randomized 512K blocks, it drops to 49.5MB/s. Going to randomized 4K blocks — nearly all seek and setup time, very little time spent on data transfers — I see 594KB/s reads! Ouch!

RAID actually makes seek times slightly worse for random access. Not for sequential access, because your blocks much longer, drives of course read in parallel. But for random jumping around on disc, the file system has to wait on the worse case of all of your drive seek times before it can return the whole block to the system.

DAW systems usually let you set the buffer time for each audio channel, which lets you tweak latency vs. throughput… increase latency, increase buffer size, and you get more tracks at the same time. Reverse that, and you have low enough delay, eventually, for overdubbing and live performance. Unfortunately, Vegas doesn’t have obvious tweaks or other settings to suggest just how much memory it’ll use during a render.

And there’s another one… forgot about that. Check your Dynamic RAM Preview settings. When this is too large or too small, Vegas slows down. This is primarily a setting for editing, anyway, but Vegas does seem to use a bit of it during rendering. I currently have mine set at 200MB; low, but it works fine. I did a few tests on this some years ago, and proved that it does have an effect — going too large, like 1GB or more, can make things slower. Unless that’s been fixed recently…

-Dave

[Don Cobble]

Ok Dave – You lost me on that last explanation. So If it is the HDs that my project is on should I go to 4 drives raid 0 or are you saying I can distribute (by type) video assets across other drives so I have many drives feeding the project. I will but drives happily if it will speed up my work.
I think my mother board does no have enough 6g satas to go with a 4 drive raid zero unless I drop down to 3g sata ports I have 4 i can use?
What do you think?
or switch to adobe?

PC 1
I7 2.8 Ghz 8GB Ram
Win 7 Pro 64bit OS
PNY Quadro 4000
PC 2
I7 3930K 3.2Ghz
32 GB Ram
Win 7 Pro 64bit OS
PNY Quadro 4000

3-4 TB HD
Vegas 10 64bit & Vegas 11 64Bit & Vegas 12 & Adobe Production Premium CS5.5.2 & Avid Media Composer 5.5

Camera
Sony EX1 shoot in 1920×1080 30P

[Russ Froze]

Yes I found I can import the dng files directly into Vegas Pro and edit them as needed. It is sluggish to respond, color space I leave at default and the built in color correction is not the greatest for the job. Still it is faster than transcoding in say Davinci Resolve. The trick is to install the adobe dng codec for windows it can be found at the following url and works with every version of Vegas video Pro from version 9 and up to 13. Let me know if this works for you as it does for me, I have re created and succeeded in importing dng and cdng into Vegas Pro on three different machines now.
https://www.adobe.com/support/downloads/detail.jsp?ftpID=5495
Russ Froze