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theskyisthelimit

VAS usage with XP11?

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Curious if anyone has been monitoring VAS with XP11 with some "moderate" addons running?

 

I believe in one case I spotted online, through using process explorer it appeared that with NYCX at least, memory usage was approaching 15GB..

 

In my system i currently have 16GB of memory.. contemplating adding 16GB more.. perhaps its just a no brainer, or maybe the one test was a fluke.

 

Curious overall what everyone is finding... i hope to do some testing this weekend on my own system.

 

 

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Nowhere near that.  At high settings with HD mesh, etc., I'm seeing < 8 GB.  Maybe NYCX is unsual though.

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:Shame On You: please don't use the word VAS, it reminds me of the dark moments I had with the other sim... :P

 

Joke aside, I've never seen mine go beyond 12gb with all the goodies out there including UHD mesh

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Well, I only have 12GB at present and XP11 quits multiple times when I fly over LFPG or hopping more than a few airports in one session. So it can definitely bust 12GB of memory. 

 

I don't blame XP11 though at all and I'm happy to see it uses my memory to the fullest. I'll build a new PC soon and 32GB will be mandatory, with option to expand to 64GB. 

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Like others, I haven't seen going beyond 12GB (uhd, orthos, payware, etc).

I also have 16GB of RAM, hopefully that should be enough :)

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X-Plane hardly even needs VAS, it directly addresses any and all available RAM since it's 64-bit. Plus, all of those airport scenery packs—they technically use up VRAM (textures, shadow rendering, etc), not RAM. It's mainly the meshes, and aeroplane add-ons that go into RAM. And complicated meshes jack up the RAM usage.

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XP usually sits around 15-16GB RAM usage for me and well over 5.5-6GB of VRAM. I have seen it hit into the high 20's but that is rare. X-CSL will hog a ton of memory at higher resolution settings with XSB. I actually had numerous OOMs because of this until I figured out what was the cause.

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if your pc can handle uhd mesh then more than 16 is always a good idea.

 

The problem is not always x-plane. the problem is what do you do besides x-plane. Just with x-plane you might be fine, but then you have firefox open with 2-3 tabs of your navigraph charts, you have plan-g open, maybe even youtube or other entertainment forms during cruise, and voila another 4 gigs of ram used without x-plane.

 

Personally i upgraded to 32gigs and with the current prices of sub 100€ for even ddr4 its a pretty no brainer.

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NYC X is extreme.  I have tested with HD Mesh version 3 and default cities and larger airports with things like Pilot2ATC and XEnviro running.  I have never had more than 8 GB VAS usage, and usually more like 6 GB or less.  I do, however, get to 7 GB VRAM use in 4k.

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I have never had more than 8 GB VAS usage

 

As said before, X-Plane 64bit doesn't use VAS (Virtual Address Space). It uses RAM, and VRAM. That's all. I think it's important to use the right terminology, VAS is a thing of the past and operating systems and software will rapidly obsolete the 32bits memory addressing.

 

cheers,

Pascal

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I agree about the VAS terminology. It refers to a fixed 4GB address space in another sim, and doesn't have anything to do with the way X-Plane works.

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Well, to be precise: VAS is active and works with 64 bit programs, but outside of the 32 bit area it doesn´t contain any usefull user information.  In 64 bits its limit is now 128 TB.

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Well, to be precise: VAS is active and works with 64 bit programs, but outside of the 32 bit area it doesn´t contain any usefull user information.  In 64 bits its limit is now 128 TB.

 

So, I have to chuckle, who's going to be the first to max out 64 bits and need more???  And will I still be able to see the screen or even alive haha

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If I remember correctly, it takes about 20 years for us to go from 1MB to say 128GB max ram on PC today. So from 128GB to 128TB may not take as long as 20 years.

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If I remember correctly, it takes about 20 years for us to go from 1MB to say 128GB max ram on PC today. So from 128GB to 128TB may not take as long as 20 years.

 

It may not, although to the extent any of this is graphics-related, there is a limit to how far you can go in pixel resolution on a big screen (or in VR) before you're just wasting pixels. An 8k monitor or the equivalent in a VR headset may top out what anyone really "needs" in resolution. 

 

Of course, that kind of thing has been said before, so who knows. Maybe the next step is a direct implant to the visual cortex, and we'll need something higher than our eyes can resolve.

:wink:

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I flew in Spain today with HD mesh, Pilot2ATC, xEnviro and the CRJ-200.  Settings all high to max.  X-Plane 11 used 3GB of RAM. The system used well under 6 GB.  I just don't see any way that the normal user would exceed 16 GB unless flying in an extreme custom scenery area like NYCX.

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I flew in Spain today with HD mesh, Pilot2ATC, xEnviro and the CRJ-200.  Settings all high to max.  X-Plane 11 used 3GB of RAM. The system used well under 6 GB.  I just don't see any way that the normal user would exceed 16 GB unless flying in an extreme custom scenery area like NYCX.

 

Nope, I will always be using at least 10GB even in the middle of nowhere.

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Regarding VAS - All Windows Programs use VAS, With a 32bit OS, all Programs Running Share 4gb Virtual Address Space . With a 64bit OS a 32bit Program can have up to 4gb of its own Virtual Address Space . I would be interested to find out How a 64bit Program, Running in a 64bit OS actualy uses Virtual Address Space ?? - Johnman

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Regarding VAS - All Windows Programs use VAS, With a 32bit OS, all Programs Running Share 4gb Virtual Address Space . With a 64bit OS a 32bit Program can have up to 4gb of its own Virtual Address Space . I would be interested to find out How a 64bit Program, Running in a 64bit OS actualy uses Virtual Address Space ?? - Johnman

 

VAS isn't a term I've ever heard used in X-Plane, even when it was a 32-bit program. That's Microsoft Flight Simulator terminology, and I wish we could avoid it here.

 

Every new version of Windows ramps up the amount of RAM it can use, and we're nowhere near the theoretical limits for a 64-bit architecture. Hardware is the bottleneck. Here's where we are right now on Windows 10, and the amounts are lower on Windows 7 (remember X-Plane supports Mac and Linux too, and I don't have those numbers):

 

Windows 10 Enterprise 2TB
Windows 10 Education 2TB
Windows 10 Pro 2TB
Windows 10 Home 128GB
 
X-Plane 10 and X-Plane 11 will currently use somewhere in the neighborhood of 8 to 32 GB of RAM depending on what scenery you're running, like the RAM-intensive free UHD terrain mesh. 
 
The X-Plane page for recommended system requirements states that you should have 16-24 GB RAM or more for the best (recommended) experience with the simulator. They're not kidding. You'll use it, if you have a strong enough system that can run UHD terrain and complex city and airport files. Plus, some overhead for any new plane models with complex systems that appear during the XP11 product cycle.

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I flew in Spain today with HD mesh, Pilot2ATC, xEnviro and the CRJ-200.  Settings all high to max.  X-Plane 11 used 3GB of RAM. The system used well under 6 GB.  I just don't see any way that the normal user would exceed 16 GB unless flying in an extreme custom scenery area like NYCX.

If your RAM usage is constantly below 4 GB with XP11 and - supposedly - HD Mesh Scenery v3, then you might need to re-check if your HD Mesh Scenery v3 installation works at all (because this very low RAM usage might be a hint that it is NOT working)!

 

There are instructions which help you to check out if things are working as expected:

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Well... it's not really that hard to understand.

 

In a 32-bit OS, the maximum allowed addressable memory is utilizing 32-bits - which means, 4 GB of addressable memory addresses - since the highest number you can write with 32-bits is (storage wise) 4 GB. Think of FAT-32 which can't handle files over 4 GB in size - same principle... A 32-bit application running on a 32-bit OS, can potentially assign 4 GB of memory - however, since the OS can't handle/understand memory over 4 GB (so it doesn't matter if you have 16 GB of memory in a computer running 32-bit OS - it still won't see more than 4 GB), the maximum allowed addressable memory for an application in a 32-bit OS is around 3,5 GB - since Windows reserves some memory for the OS itself.

 

When upgrading to a 64-bit OS, the allowed addressable memory is expanded to 128 TB. However, 32-bit applications (or threads) are still contained within the 4 GB limit. Some applications, then launches multiple threads - which each have 32-bits of assignable memory addresses available (or 4 GB of memory) - per thread.

 

A 64-bit application has expanded the addressable memory to 128 TB (per thread) - just like the 64-bit OS has. So a 64-bit application could potentially max out a 64-bit OS, and you would get an OOM - provided you have 128 TB of memory available. Which I don't think many people have... 

 

That's the way I understand it, anyway...  :smile:

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 I would be interested to find out How a 64bit Program, Running in a 64bit OS actualy uses Virtual Address Space ?? - Johnman

IIRC, every program (or better process) is using VAS, no matter what the combination of 32/64bit is (OS/application).

The process "sees" it's VAS, while the OS is responsible for mapping this VAS to the  physical memory. Of course the VAS on 64bit OSes can be as large as 128TB.

 

OOMs are (and will always be)  possible if the PC has less RAM than what is requested by the sim, no matter if we are running 64Bits or not. Or let's call them OORs (out of ram), because I guess the OS will then start mapping part of the VAS to the pagefile, which is something you's probably want to avoid for performance.

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