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Dougal

Question Re Vertual Address Space?

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After shutting down all non essencial services, processes and apps, prior to launching FSX, is there a way to then work with the VAS like there is with HDDs and RAM - like defragging perhaps?

 

I understand the VAS required by FSX must be contiguous, so is there a means to achieve this?

 

Ta!

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I'm guessing if there was, we would of been doing this years ago. Running in DX10 is the only best bandaid we have I think.

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I've been wondering this too. There are programs like Alacrity that will defragment memory. This doesn't apply to VAS? There is no easy way to tell because programs like Procexp only tell you how much VAS is being used, not whether the remaining VAS is fragmented or not. And yes, I think I know the answer, it would be way to easy a solution, but it doesn't help to hope lol.

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Dougal

In practice you cannot alter the VAS in any shape or form.

It is a set of dynamic virtual addresses set up by the OS - fresh each time (Nothing to do with Physical RAM or the paging file) to load a program like FSX so that if FSX becomes damaged or corrupt it does not bring down the whole OS. It also serves as a repository for the code that will be passed to the cpu/cache/ram/gpu as called.

For a 32-bit app with Large address aware set running in a 64-bit OS it has a maximum value of 4GB, (but for example X-Plane 64-bit can address 8 terabytes of VAS), Even as little as 1MB fragmented at the wrong address can reult in a Windows OOM error.

It can be monitored with VMMap and that is is very interesting to see what happens to the VAS whilst FSX plus add-ons are running.

I did some experiments with a windows server registry hack called "HeapDecommitFreeBlockThreshold" and got that to work in a 32-bit OS but I could not find the correct parameter for a 64-bit OS. http://support.microsoft.com/kb/315407

WRT FSX the VAS is small and complex and the best solution IMHO is a 64-bit app in a 64-bit OS.

Regards

pH

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After shutting down all non essencial services, processes and apps, prior to launching FSX, is there a way to then work with the VAS like there is with HDDs and RAM - like defragging perhaps?

 

I understand the VAS required by FSX must be contiguous, so is there a means to achieve this?

 

Hi Phil, Try this...http://en.wikipedia.org/wiki/Process_Explorer. This free program, is sort of like Task Manager on steroids. As you may know, in Task Manager, you can select the performance tab, then Resource Monitor, then chose from several tabs, eg, memory to see where all the memory is being allocated. If you select the disk tab, you can see how the various cores are coping.

 

Now, if you download the above program, Process Explorer, it will show you in detail where all the memory is being used. For example, when your computer is idling away, you can see the difference when you you start FSX, then, then load say the PMDG 737NGX, then go to a ORBx airport, I often use YMML, get REX weather setup and you can see where the memory is going. The if you click on the FSX instance, it will open the bottom screen and you can see what DLL or what ever is called by FSX while you are using FSX it you use windowed mode. Also, by double clicking on the FSX instance, you will also bring up its properties, which shows a wealth of information. In the example pic, I have used the Tutorial No2 for the 737NGX. The memory indicated is quite low, this is because I have loaded the tutorial at this point, which means the memory load has not had time to build up through the the flight. Usually, by the end of the flight after landing ay LOWI, the FSX memory usage is indicating approx 2,200,000 Private Bytes.


Geoff Bryce

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