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can FSUIPC clear VAS to avoid OOM?

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Hello Pete, my name is Chris Bell

i have a question in regards to VAS OOM and FSUIPC


FSX scene is growing to the point we are pushing scenery to the max now

with latest hardware developments we enjoy a great SIM

but we now have a new issue to deal with VAS OOM


would it be possible somehow to utilize FSUIPC to clear/purge VAS midflight in FSX?


as it stands; there is no tool out there that can do this

developing such capability will give FSX users desperately needed life support; with latest scenery developments











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would it be possible somehow to utilize FSUIPC to clear/purge VAS midflight in FSX?


There's obviously no way to free allocated memory without causing FSX to crash when it comes to access it. And there's no way to detect memory which should have been freed up but isn't (that would only occur with buggy software, aka "memory leak")..


If you mean simply consolidating fragmented free memory into larger portions, I really don't think that always helps -- free memory is free memory even when apparently fragmented.  Certainly, if it makes the largest contiguous block very small (less than a page) it will cause OOMs, but the problem with memory defragmentation is that it has to be done with exclusive memory access and can take many seconds. Are you going to allow FS to pause to do this? You can't really spread it out imperceptibly. If you tried you'd simply introduce continuous stutters.


as it stands; there is no tool out there that can do this


There are programs which try to sort this out. Here's an extract from IOLO's "System Mechanic" publicity:


4. Defragment memory

Defragmenting memory reclaims and frees up valuable memory, which can have a dramatic impact on speed. Defragmenting the memory can also improve the stability of your computer as low memory is a common cause of computer crashes and lockups.


System Mechanic: Navigate to the Individual Tools pane. Under the Increase Performance category, click Start next to Defragment Memory. You can run and view an analysis of your PC's current memory usage and then run the defragmentation. After a short pause (~20 seconds) as the system reallocates memory, you will see how much memory was reclaimed.

ActiveCare in System Mechanic: To have System Mechanic automatically defragment the memory when it is detected as being low, enable Automatically repair low memory problems on the Automated Tasks pane.



See the bit about a "short" pause --- around 20 seconds?


Try that program if you like. See if it helps. I have serious doubts.


I have only ever suffered from one occurrence of an OOM, and that was a memory leak bug in a driver I was writing for my own cockpit, easily fixed




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i have doubt as well, third party tools can't clear FSX VAS usage


Nothing can clear allocated memory without crashing the process concerned. Identifying allocated memory which is no longer needed is impossible -- only the programmer knows what he's finished with.


Defragmenting process memory which is so far unallocated is not only diffcult, it takes the same sort of time that System Mechanic would take. Thus freezes or stutters.



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