Kommentare

Cliff Etzel schrieb am 05.11.2009 um 23:02 Uhr
my understanding is rendering is CPU dependent - faster CPU, more cores = shorter render times

Cliff Etzel
Videographer : Producer : Web Designer
bluprojekt
srode schrieb am 05.11.2009 um 23:46 Uhr
Ram preview will improve proportionately - I doubt any render time difference above 6GB
Aje schrieb am 06.11.2009 um 08:44 Uhr
Another RAM question.
Vista 64, CPU Q9550, Vegas 9c/64 and just got 8GB RAM .
Working mostly with AVCHD or intermediates (scene avi´s)
from 3 cams
How much dynamic RAM of those 8 GB
will I give Vegas 9c/64 for optimal preview?
Is it important to use multiples 256,512,1024,2048.......
or can I just use, say "4GB"?
I know that the Vegas preview RAM issue has been discussed
here since my first version Vegas 3 but I have never got as much
as 8GB RAM to play with before and would like to know how
you folks would do in my situation.
/Aje
srode schrieb am 06.11.2009 um 08:57 Uhr
It will let you use as much as you set the limit for in your options - if you had 24GB installed and you set it for 23 it would let you use 23gb
jabloomf1230 schrieb am 06.11.2009 um 13:20 Uhr
The rule of thumb is to have a minimum of 2 GB RAM for each CPU core.
daryl schrieb am 06.11.2009 um 13:51 Uhr
jabloomf1230, that makes a TON of sense, never thought of it that way. Thanks!
rmack350 schrieb am 06.11.2009 um 15:08 Uhr
Okay, so taking this rule of thumb with a quad core and then adding in the question of preview RAM, would the rule of thumb be 8GB for the quad and then whatever you have above that for the preview RAM setting?
Aje schrieb am 06.11.2009 um 15:25 Uhr
"It will let you use as much as you set the limit for in your options - if you had 24GB installed and you set it for 23 it would let you use 23gb"

OK I understand the figures but Vegas preview RAM use has been very odd as I´ve understand.
I´ve seen advices here of setting it to no more than 512 even if you have a lot more to use becuse Vegas cannot handle it - is that not an issue with Vegas 9 anymore?

Can Vegas preview really use 23 GB RAM if I had it?
/Aje

jabloomf1230 schrieb am 06.11.2009 um 17:12 Uhr
Of course, for video work, you can never have too much RAM. The rule of thumb does not override or replace specific information about how your NLE and associated codecs and plug-ins use multiple cores and physical RAM. On the other hand, it makes no sense to starve a quad core or greater computer, by having all the cores share a small physical RAM address space.

It all boils down to two factors. How much cash to you want to spend on RAM and how much RAM will your motherboard hold. If the absolute length of RAM previews is a major goal, then buy all the RAM that will fit on the mobo.
rmack350 schrieb am 06.11.2009 um 17:14 Uhr
The devil is in the details.

64-bit Vegas on a 64-bit OS, all on a motherboard loaded with 24GB of RAM, could probably be set up to use 23GB for RAM preview. Maybe more if there're no sanity checks in 64-bit Vegas.

32-bit Vegas, on the other hand, is designed to use 2GB of RAM so setting a preview RAM setting too high will eat up too much of the RAM Vegas would otherwise use to operate. Add to that the fact that 32-bit Vegas is usually used on 32-bit Windows so the maximum physical RAM you could possibly have for the entire system is limited to about 3GB. So if you set the preview RAM setting real high something is going to have to be shuffled off to the systems page file. It might not be Vegas, it could be part of the OS, but as long as there's page file activity Vegas is probably going to slow down.

The original question is whether 8GB will allow you to render faster than 6GB. The answer is "maybe". Some things seem to starve and crash Vegas so if you find that you can't completely render your big project with 6GB but 8GB solves it then, yes, your render is faster.

And if you watch Task Manager and you see your system's page file growing and growing while you render then adding more RAM will make the render go faster because it reduces your need for a page file.

And of course if you had 20GB worth of cached frames sitting in prerender RAM then that part of your timeline would render really fast. Depending on how big the total project is, having a huge preview RAM setting might or might not make a difference in render times.

However, if I had 4 cores and 24GB of RAM and was following Jabloom's rule of thumb then I'd assume 8GB should be reserved for basic operations and the other 16GB was up for grabs for the prerender. That's still pretty good.

Rob Mack
rmack350 schrieb am 06.11.2009 um 17:16 Uhr
I've never heard that multiples make a difference. As far as setting a size, I'd watch Task Manager and if my page file was growing I'd reduce the prerender RAM setting.

Rob
MPM schrieb am 06.11.2009 um 19:44 Uhr
>"All other things being equal, will I notice a differennce in rendering times
>upgrading to 8GB memory over 6GB memory?"

Totally FWIW, in life nothing is truly equal :?P

7 64 likes RAM, your m/board has a max limit, & you have X number of slots & channels -- fill them in the way that makes the most sense to you & your situation. More is ALWAYS better, but you face diminishing returns the more you add over the optimal amount for your board & CPU. You can get an idea of what that magic number is by reading reviews & O/C &/or hard core gaming forums. You can do the same for brands/models of RAM.

If you're running AMD channels might not make as much difference, but otherwise balancing your sticks over however many channels can help. OTOH, it can make good economic sense to fill some minimum number of slots today, if RAM is going to drop in price tomorrow, when you can fill 'er up with the minimum amount of pain to your wallet.

When it comes to video, how much X amount of RAM gives you a boost depends on what you're doing, assuming you've got enough to keep the rest of your system happy. Encoding, where you're chiefly moving video from here to there, might go faster if you invested part of your budget in SSD rather than DDR2/3. Working with [especially large] images before you encode might rather you had bought more/bigger sticks of RAM.
richard-amirault schrieb am 06.11.2009 um 22:43 Uhr
The rule of thumb is to have a minimum of 2 GB RAM for each CPU core.

Is that "real" cores or is that hyperthreaded cores?

My new i7 has 8 cores in Task Manager .. but I only have 12 gig of ram. (have yet to edit anything 'serious' with it ... and don't own any HD gear .. yet)
Salamander schrieb am 07.11.2009 um 10:55 Uhr
This has been helpful. Thanks!
jabloomf1230 schrieb am 07.11.2009 um 14:07 Uhr
Hyperthreading is actually more like "Hype" er threading. This means that each physical core can run two parallel blocks of code at the same time. Of course, if these two threads are independent (like what you encounter in video encoding and decoding), each physical core runs each thread at half the speed of running a single identical process on that core. In other words, hyperthreading speeds video work up very marginally, if at all. It does allow the computer, technically, to do 8 independent tasks at once, so there is some advantage if the software is written to handle hyperthreading.

Basically, you have 4 cores and 3 GB/physical core, which for the next year, (ha ha) should be fine. It's always fun to look back at these discussions a few years later, to see how far the hardware has advanced. It seems like only yesterday that a dual core PC with 2GB RAM and a 250 GB hard drive was a "monster". Now, it's just what you see on shelves of a big box store selling for 20% off.
MPM schrieb am 07.11.2009 um 15:04 Uhr
>"It does allow the computer, technically, to do 8 independent tasks at once,
>...if the software is written to handle hyperthreading.

Building on that, in case it's helpful to the less tech-oriented...

Traditionally PCs/laptops did one thing at a time, but did it very, very fast, so you wouldn't know that whatever you were doing was being constantly interrupted by mundane tasks like talking to your mouse. And it was fine, until CPUs got to 3 gig & they found that they couldn't make huge leaps in speed anymore -- the answer to get you to upgrade was dual core & then quads & so on. In XP it didn't make a huge difference, but Vista really liked multiple cores -- why IMHO huge numbers of users tried Vista on their XP machines & loathed it. While Vista/7 use if not depend on multiple cores, what about your other software?

Depends... The prob with using more than one core &/or CPU is timing. When you're processing video (& most everything else), stuff has to be done in order. Video might have to be re-sized before it's encoded & there's a definite order to the frames to name a couple of Very simple examples. Another way to explain (over simplified) what happens is when my wife & I go for groceries we either take longer by sticking together, or she'll grab some items while I grab others... the 2nd is faster, but then I have to either hunt the isles to find her, or one of us waits at checkouts for the other to show up. Multi-core CPUs go through the same thing. The problem designing & using them is getting the workload split up, & then putting everything back together in proper form.

My real life experiences totally FWIW, was a single core stank when asked to run Vista, while *much* slower dual cores in laptops do fine. At the moment I'm running a quad in 7 64 & XP 32 -- encoding in several apps in 7 uses more than 1 core, while most in XP use 1. Speed (fps) encoding remains about the same -- same system, same app, same video, different OS. Vegas uses 4 in either. IF the task can be efficiently split up over 2, 3, or 4 cores/CPUs, & if the coders have taken the time/trouble to split things up, & if they've done most things right, you should see a performance boost. If not, then a higher speed dual core could be faster than a slower quad, even if it [the quad] has hyper-threading.

Always remember, Intel's true goal [besides maybe world dominion ;?P ], is to get more, newer, *better* chips sold.