I see a lot of confusion regarding this memory thing and I'd like to help a bit. Others have said this as well but the point needs to come across:

 

And you arent helping with this incorrect description. VAS has nothing to do with the physical amount of memory you have. Not on the GPU or system RAM.

 

There are many accurate descriptions regarding VAS and OOM's in this very P3D forum alone.....this is not one of them.

From the perspective of an interested bystander, i kind of thought that one of the main advantages of this was supposed to be less tweaking.........

 

Instead, it already sounds kind of like tweak-fest 2013, which is kind of disappointing. (FSX chuckles from tha' grave)

 

It will be interesting now to see how LM responds to this.

 

Indeed...

 

I'm pretty sure this is only true if you're running a 32-bit OS.

 

People need to post their setups including their OS. Relax the signature rules on the forums while we are looking at P3D v2.

This is all sounding like many addons are having issues. They may install and run, but they don't know how to behave well with DX11. Runs great in dx9 and fsx but different animal in p3d. Everyone had awesome performance a week ago, now all these reports coming in of tanking FPS. 3PDs have to play catch up now and update products to play nice with DX11 while LM has to do their own backend optimizations and fixes.

People need to post their setups including their OS. Relax the signature rules on the forums while we are looking at P3D v2.

 

Um, there's a perfectly good place on your profile for that, and I've been using it when reading topics about P3D2. It only takes a click.

 

 

People need to post their setups including their OS. Relax the signature rules on the forums while we are looking at P3D v2.

 

Look under most peoples user names at the left. There is 'My PC' and 'My Simulator' just click on them and it gives all that info as long as the user has set it up. No need for huge signatures.

I'm pretty sure this is only true if you're running a 32-bit OS.

The issue is not RAM or VRAM, but VAS. Even if you use a 64 bit OS, VAS will be limited to ~4GB for any 32 bit application.

 

From Wikipedia:

 

Virtual address space (VAS) is the set of ranges of virtual addresses that an operating system makes available to a process.

 

On a 32-bit Microsoft Windows installation, by default, only 2 GiB are made available to processes for their own use. The other 2GB are used by the operating system. On later 32-bit editions of Microsoft Windows it is possible to extend the user-mode virtual address space to 3 GiB while only 1 GiB is left for kernel-mode virtual address space by marking the programs as IMAGE_FILE_LARGE_ADDRESS_AWARE and enabling the /3GB switch in the boot.ini file.

 

On 64-bit Microsoft Windows, processes running 32-bit executables that were linked with the /LARGEADDRESSAWARE:YES option have access to 4 GiB of virtual address space;without that option they are limited to 2GB. By default, 64-bit processes have 8TB of user-mode virtual address space; Linking with /LARGEADDRESSAWARE:NO artificially limits the user-mode virtual address space to 2 GB.

Imo the over-riding theme is that it is only NOW that p3d v2 has entered beta phase...and we (well you cos I've held back from buying for this reason) are now paying to beta test it.

 

Doesn't seem like such a good idea to have only developers beta testing to me as its not very balanced.

 

I'm not knocking those devs that were beta testers at all....but let's be realistic that each individual dev is only really gonna have tested their own products aren't they-I mean why would a scenery dev (FTX for example) test alongside a weather engine dev (Opus for example)??

 

Seems that its only when WE throw all those individually tested products (and there is also a HUGE difference between p3d v2 ready and p3d v2 optimised but that's another thread!!) into the mix together that the issues are becoming apparent!!!

 

And that worries me a little!!

 

Regards

 

Steve

 

 

I'm pretty sure this is only true if you're running a 32-bit OS.

 

As the post above already states - that's not correct.

 

And you arent helping with this incorrect description. VAS has nothing to do with the physical amount of memory you have. Not on the GPU or system RAM.

 

There are many accurate descriptions regarding VAS and OOM's in this very P3D forum alone.....this is not one of them.

 

I know very well what VAS is. I didn't say VAS was directly RAM or VRAM. I said there was a hard limit of 4GB which included both. This is correct.

 

I was my impression that many wondered whether buying a video card with more memory will stop OOM errors or perhaps somehow bypass the memory limit of the 32 bit application. Under the constrains of VAS if they have more than 4 GB total memory (RAM + VRAM) then more VRAM will (mostly) only help with speed, but not stability.

I've been pushing my hardware pretty hard (mid-low range CPU with a relatively fast card) but am running Win 8.1 without hitting OOMs (I get terrain spiking if I push past "the wall", but still no OOM after a 4-5 hour flight with heavy autogen). 

 

I know memory management was a focus for MS when developing this OS, and I wonder if others running Win 8.1 can comment on their experiences...

I see a lot of confusion regarding this memory thing and I'd like to help a bit. Others have said this as well but the point needs to come across:

 

Since FSX and Prepar3D are 32 bit applications the maximum amount of memory they can use (RAM and VRAM together) is 4 GB.

the last sentence is totally wrong and will increase the confusion. This has been explained ad nauseam in other posts.

I was my impression that many wondered whether buying a video card with more memory will stop OOM errors or perhaps somehow bypass the memory limit of the 32 bit application. Under the constrains of VAS if they have more than 4 GB total memory (RAM + VRAM) then more VRAM will (mostly) only help with speed, but not stability.

Under no circumstances will VRAM ever affect the application's VAS table. That is reserved exclusively for the running application (P3D in this case).

 

Anytime VRAM has to be "shadowed" it uses the operating system's VAS, which should never occur when using DX10 or DX11 rendering.

I know very well what VAS is. I didn't say VAS was directly RAM or VRAM. I said there was a hard limit of 4GB which included both. This is correct.

I'm afraid you don't. VRAM is not included in VAS.

Ok, so I downloaded Process Explorer to check P3D's VAS. I loaded my troubled flight and started of with around 2.200.000. That's with the A2A C172, FTX Global, Norway freeware and rotten weather. After setting autogen to Extremely dense (coming from Very dense) VAS went up to around 2.800.000. So I did what I did yesterday and that was looking around a lot, making jerky turns while speeding over the treetops. Sometimes VAS would go up 2.900.000 but I couldn't get it much higher.

 

And then SUDDENLY... OOM. PE showed 3.658.888. I didn't do anything special, I didn't fly over new terrain with some addon airport, I still was in the same surrounding!

 

I tested this a few times more and everytime VAS would jump from something like 2.850.000 to 3.550.000 and I got an OOM.

 

Now I thought that VAS usually slowly builds up. I remember reading about a VAS warning in FSUIPC that would alarm you when you got close to VAS. But all I seem to get is a SUDDEN and totally unexpected JUMP to an OOM. The lowest value that PE showed and that lead to an OOM was 3.551.396.

 

Obviously it's pretty hard this way to find out WHAT is causing the OOM since the jump is so sudden, without anything obviously loading. Another problem is that the OOM comes with various settings. I tried for instance to figure out what happened when I used a higher tessellation setting: one time the OOM came pretty quickly after doing so, but the next time I did not even touch tessellation!

 

Am I right in thinking that VAS should slowly build up? If so, does anyone know what may cause that sudden jump in VAS?

 

P.S. CPU usage was around 25 to 25%, GPU usage was 100% all the time.

 

EDIT

Tested some more to see what a few settings would do with VAS. Turning on shadows fr buildings and vegetation did hardly make a difference. At one moment I set a lot of things full right and VAS went just over 3.000.000 but no OOM. Then it suddenly OOM'ed but while VAS was only 3.150.000 according to PE...? I don't get it: isn't that way too low to get a VAS...?

Jeroen,

 

You need to remove some of your addons and test. You are not being in any way fair here with your testing as it stands.

 

it has already been determined that there are indeed some differences and incompatibilities that will present with FSX addons moved to P3D2.

 

My opinion may be meaningless to you, and that's certainly fine, but I won't take any more of your results seriously until you start taking your testing seriously. Forcing a test situation with addons that may or may not be compatible, and then lamenting the results, is not a proper test for any situation.

Repeat the same experiment using the A36 instead. That will at least get the reportedly not-really-P3D-ready A2A C172 out of the equation.

 

Never run any experiment with multiple variables...

 

I see that Brian already said pretty much the same thing using more words... :Big Grin:

 

Personally, my advice to everyone would be to first get P3D v2 running well all by itself, using only what came in the download.

 

Then, and only then, install a single add-on and run some controlled tests without fiddling with P3D's settings.

 

Then after some careful consideration, change one thing at a time to see the results. Always reset to your baseline configuration before testing any new changes, otherwise you won't know which adjustment made the largest improvement, and you'll soon be completely lost.