FSX is a different story. Most people should never hit their memory limit in FS9. I think more have memory leaks than anything else. With all the great freeware scenery out there, it only takes one bad file. Sadly, there are a few files I've found here which cause problems. I even had a scenery I was trying to create causing issues and I was never able to figure out why. I eventually just had to scrap the entire project.There's also the issue of that EXE mod we're not allowed to talk about. People might find an older version of the EXE which is not patched to 9.1 which brings the memory leak back into play which was fixed years ago. I think that people should try disabling 3rd party scenery first and then get into extremes later on. People talk like these OOMs are something that are going to happen, and that's not true. I haven't seen one since the 9.1 patch came out, and I ran 32bit XP for the longest time. The worst thing people can do is make assumptions when diagnosing a problem.

I agree, even some well known add on developers had memory leak's in their packages (VHHX by FlyTampa, now fixed mind you and Aerosoft with Casablanca to name two off the top).For me it wasn't that way. I was running into OOM errors since the Coolsky MD80, only when flying in North America (with Ultimate Terrain). I could do all the flights I wanted in the LVD or the PMDG 747 from NA to Europe but if I did it the other way around (Euro to NA) I would get an OOM error (of course I had UT for USA/CAN and not for Europe, so the added features if UT were pushing the limit).So with the default FS9 I'm sure you may not be pushing that 2GB 32bit OS limit. But add in Ultimate Terrian, add on traffic, add on scenery and then a complex airline like PMDG 747 and your pushing the limit. So the way I figured it was get rid of the add on's or get a 64bit OS.As I said before since I switched to 64bit I have yet to have an OOM error flying anywhere with anything and I have thrown the kitchen sink at FS9 as far as add on's go.

That is indeed one of the possibilities discussed there, I'm not sure how that makes it "incorrect".John

What's incorrect is the suggestion that patching the executable file by itself solves any problem. Addition of the LARGEADDRESSAWARE flag to the executable's PE header does *nothing* if the 32-bit OS is not also configured to permit applications to access greater than the default 2GB limit imposed by Win32 in all its variants.There are a lot of esoteric unknowns in FS tweaking, it is true, but the behavior of Win32 with respect to application address space is well-documented and well-defined.RegardsBob ScottColonel, USAF (ret)ATP IMEL Gulfstream II-III-IV-VColorado Springs, CO

What's incorrect is the suggestion that patching the executable file by itself solves any problem. Addition of the LARGEADDRESSAWARE flag to the executable's PE header does *nothing* if the 32-bit OS is not also configured to permit applications to access greater than the default 2GB limit imposed by Win32 in all its variants.There are a lot of esoteric unknowns in FS tweaking, it is true, but the behavior of Win32 with respect to application address space is well-documented and well-defined.RegardsBob ScottColonel, USAF (ret)ATP IMEL Gulfstream II-III-IV-VColorado Springs, CO

Well, the truth is that for me applying your solution caused a lot of problems for me in terms of constant disk-thrashing causing great pauses in the game on two different computers. I didn't twig what was causing it for quite a while. I eventually removed that additional entry and everything ran ticketyboo and I have not experienced the once frequent OOM error in the couple of years since applying the patch, despite having probably doubled the number of installed sceneries since then.So I keep an open mind on the subject and, I'm afraid, will not be bullied by "those who know" saying it will not work. That web page of mine suggests trying it, it does not say what it right or wrong and gives no finite orders to anybody.Note also that the supplier of the patch makes no reference at all to having to change any other settings to use it.John

I agree, even some well known add on developers had memory leak's in their packages (VHHX by FlyTampa, now fixed mind you and Aerosoft with Casablanca to name two off the top).For me it wasn't that way. I was running into OOM errors since the Coolsky MD80, only when flying in North America (with Ultimate Terrain). I could do all the flights I wanted in the LVD or the PMDG 747 from NA to Europe but if I did it the other way around (Euro to NA) I would get an OOM error (of course I had UT for USA/CAN and not for Europe, so the added features if UT were pushing the limit).So with the default FS9 I'm sure you may not be pushing that 2GB 32bit OS limit. But add in Ultimate Terrian, add on traffic, add on scenery and then a complex airline like PMDG 747 and your pushing the limit. So the way I figured it was get rid of the add on's or get a 64bit OS.As I said before since I switched to 64bit I have yet to have an OOM error flying anywhere with anything and I have thrown the kitchen sink at FS9 as far as add on's go.

Hi,Just one question on this. If one is running a 64 bit OS (ie Windows 7 Home Premium 64 bit) does one still need to set the LARGEADDRESSAWARE flag in the FS9.EXE file header?RegardsDaveAntwerp, Belgium

Hi,Just one question on this. If one is running a 64 bit OS (ie Windows 7 Home Premium 64 bit) does one still need to set the LARGEADDRESSAWARE flag in the FS9.EXE file header?

Yes.

Yes.

Hi,Thanks for the quick reply. So if I set the flag in FS9.EXE then I'm set to go, or do I still need to configure something in Win7?RegardsDaveAntwerp, Belgium

Well, the truth is that for me applying your solution caused a lot of problems for me in terms of constant disk-thrashing causing great pauses in the game on two different computers. I didn't twig what was causing it for quite a while. I eventually removed that additional entry and everything ran ticketyboo and I have not experienced the once frequent OOM error in the couple of years since applying the patch, despite having probably doubled the number of installed sceneries since then.So I keep an open mind on the subject and, I'm afraid, will not be bullied by "those who know" saying it will not work. That web page of mine suggests trying it, it does not say what it right or wrong and gives no finite orders to anybody.Note also that the supplier of the patch makes no reference at all to having to change any other settings to use it.John

Note that I do not recommend use of the /3Gb switch...I recommend switching to use of a 64-bit OS instead as the best solution for persistent OOM errors. The /3Gb switch and USERVA settings allow some reallocation of memory address space between system and applications, and often does result in excessive disk thrashing due to paging parts of the OS in/out--code that would otherwise remain resident in memory. I tried it on several of my computers and NEVER had a reliable and stable configuration that was also immune from OOM errors.No bullying here. I'm telling you that if you patch FS9.exe and do not either set the /3GB switch or move to a 64 bit environment, it's nothing but a placebo. You can convince yourself that you've cured something if you want. If it makes you happy, go for it. Don't cost nothin' and nobody else will know.That said, I think it's important to do a little myth-busting so others aren't led astray. I've written about it in much more detail and linked to the relevant MS reference docs elsewhere on AVSIM if you care to research further. The placebo solution is, of course, freely-available too.

Thanks for the quick reply. So if I set the flag in FS9.EXE then I'm set to go, or do I still need to configure something in Win7?

If you're running Win7 64-bit, no further action is needed. If you're running the 32-bit version, you still have to configure the OS for 4-gigabit tuning (4GBT)RegardsBob ScottColonel, USAF (ret)ATP IMEL Gulfstream II-III-IV-VColorado Springs, CO

To simplify what Bob is saying.In a 32bit OS your limited to 4GB of Virtual Address space, 2GB for applications and 2GB for the operating system (VA space has nothing to do with your swap file or physical ram installed).The 3GB switch tells the OS upon booting up to allow 3GB for applications and only 1GB for the OS. You would also need to tell any 32bit application (in this case FS9.exe) that it can use beyond the 2GB limit that is now allowed by the OS.With a 64bit OS by default the virtual address space is NOT limited to 2GB, however when running a 32bit application (such as FS9.exe) you still need to tell the 32bit application that it is allowed to go beyond the 2GB limit.Makes sense?Here is a good read>>>http://blogs.technet.com/askperf/archive/2...ifying-3gb.aspx

Gentleman, Thank you so much for your advice and replies. I am really surprised that someone has not started a thread with a list of sceneries that may have suspect .bgl files. Anyway the conclusion I have come to (despite the alternatives which have been put so well) is simply to buy Win 7 64 bit. Thanks again. Tristan.

I am really surprised that someone has not started a thread with a list of sceneries that may have suspect .bgl files.

Diagnosing these kind of problems is guesswork at best. I'd never want to make accusations at freeware devs without being nearly 100% certain, and it is rare that I am ever sure. I can disable a scenery and maybe an error will go away, but who knows? With all the add-ons we put into it you can never be sure what the real cause was. I suppose my advice would be if you get a consistent, repeatable problem in a specific geographic area (IE fly the exact same flightplan over and see if it happens) then look towards your local BGL files. If you are getting OOMs on longer flights with complex add-ons, that's probably more for the other suggestions. Even this isn't certain, but at least can have a chance at pointing you in the right direction. -Keep a record of what you install-Don't let auto-installers run from unknown sources (most auto-installers are just "auto-extractors" so you can just dump to a dummy folder and manually copy over yourself). -Get rid of any duplicate afcads (scanafd in library)

Gentleman, Thank you so much for your advice and replies. I am really surprised that someone has not started a thread with a list of sceneries that may have suspect .bgl files. Anyway the conclusion I have come to (despite the alternatives which have been put so well) is simply to buy Win 7 64 bit. Thanks again. Tristan.

Hi Tristan,I don't think it is really a case of "suspect" files. I think you will find that scenery "A" works fine, as do "B", "C", and "D". But when you have them all running together they make too heavy demands on the system and that's when you get your "OOM" error. In the days when FS9 was created (let's be honest, it is pretty long in the tooth now) I doubt that it ever crossed MS's minds that we would be enhancing their product at the intense level that we do this many years on. As has been said, there are ways to get more out of today's technology, with computer memory at levels that were not even thought of when FS9 was born.John