RAM Quantity and Usage in MSFS

With the initial release of MSFS my memory usage often maxed out at 16GB so I felt the need to increase my RAM to 32GB. There appeared to be a memory leak as in some flights the RAM would slowly creep up to 27GB over an extended period of time. But more common was a 22GB peak. Then the major update was released (July 27th) and since then I’ve not seen it use more than 13GB.

Excellent optimisation by Asobo, but if the code can’t use more than this, even with the draw distance set to ultra, then I thought what’s the point in having more capacity than I need. 32GB always seemed like overkill, and no other app or game I have will use as much as MSFS.

As an experiment, I disabled the Channel B DIMMs in the BIOS, assuming this has the same effect as physically removing them, effectively reducing my RAM back to 16GB.

Windows boot time increased from 38s to 51s, but load times in MSFS were not really affected. interestingly, I did see the maximum RAM usage was lower (9.1GB in a landing challenge compared to 9.7GB with 32GB RAM enabled, and 9.7GB in the London Discovery Flight compared to 11.2GB). There was no noticeable performance hit, but then my FPS is locked at 30FPS so can’t confirm.

This implies that MSFS likes having a certain amount of memory buffer, but in theory I could probably just stick to 16GB. Who knows what the next major update will demand of hardware. Would be good to have a setting where more RAM can be utilised to improve performance if it’s available.

Would be interesting to hear what memory usage other people get.

(I’m running 4k Ultra on i7-9700K and GTX1080Ti)

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I have all the time.

I’d say I’m similar, I’ve definitely seen much lass RAM usage after SU5. I would be 13 to 30Gb used before SU5 (the KSTL addon is a hog) and now I don’t get past 20Gb no matter what.

I hope it’s efficiency, but I agree, if we have the RAM, let us use more to cache scenery and draw distance.

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After SU6 I saw my RAM usage increase again with the addition of the off-screen pre-cache slider. Set to Ultra and with increased LODs was using around 20GB on big cities. After the hotfix, it doesn’t use more than 10GB, like SU5. Have noticed that pop-ins are back as well

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Yeah. After SU5, 16GB RAM is suffice, unless you want to set the LOD beyond the redommended settings.

Won’t it be whatever the currently most powerful Xbox is? They won’t be releasing anything that demands more than Xbox can deliver I don’t think.

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Due to the fact I have a lot of RAM not being used, I decided to create a RAM Disk and place the Rolling Cache there. Don’t know if it will have an impact on performance, but at least the RAM is utilised.

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Considered using my 64gb of RAM as well like this. But the data will be deleted every time you shut down your PC. You will then also have to reinitialize the rolling cache each time you start the game then.
In the end it annoyed me too much so i switched it back to my SSD

Yes, there is a lot of RAM not being used by FS2020, especially if you have 64 GB.

But, Windows 10 and other Apps such as Office, etc. also use RAM.

And, Windows 10 uses RAM as Cache for the APPs
running under it, FS2020 and the other Apps.

As such, I don’t know what affect your RAM disk has on the system.

I also created a RAM Disk but did not see any difference (on my 64 GB)
and un-installed it.

Why would you think that? There are many, many games (practically all cross-platform games) that have one set of graphical settings on the console, and a completely different (and better) set of settings on PC.

Take Witcher 3, for example. The Xbox version and the PC version are the same game, but on PC you can really crank up the settings and make it look MUCH better.

Or Cyberpunk. Or FIFA. Or F1. Or Gears… the list goes on.

I don’t know why so many people think it’s impossible to have a game work across platforms and have different settings. That’s just how every single cross platform game has worked for at least the last 15 years…

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I also noticed that my VRAM is limited

But Asobo have said it will be the same. This is why there have been all the graphics downgrades since SU5 so it will run on console.

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Not sure what you’re talking about. If you can post a source where they say they will make PC and Xbox the same, please do so.

Yes, I’ve seen the interview where they talk about the technical challenges of getting it onto the Xbox and how they successfully did it. They do not say that from now, PC will be ignored.

Or you could actually, you know, try it. I have a Xbox Series X and a high end PC (3080 Ti, 5600X, 32 GB RAM, all NVME) both hooked up to 4K monitors. The sim looks a LOT better on my PC at 4K Ultra compared to the Xbox. And that’s without any mods or tweaks to config files - just Ultra settings. If I tweak the cfg file it gets even prettier.

OK, what cfg tweaks, mine is looking a lot worse since SU5?

Increasing the LOD value in the usercfg.opt file….

@gandreou

Curious to know what size page file you have?

I guess I have been wondering about the RAM strategy of the game engine like many others here.

Personally I think the usage is way too low … or way too “pessimistic”. Unless there is a lot of memory pressure in the operating system (the extreme would be paging activity) I would love the game to use more … in order to cache more data.

I do a lot of sightseeing … and so I often switch between the cockpit cam, the external view cam … and the drone cam. Now the drone often lags behind the aircraft and so the (LOD) data for that view point is typically (very) different.

This results in a cam switch triggering a very noticable “re-buildup” of the 3D assets (textures, objects etc.)
… and that process is often reeeeaaaallllly slow. The pop in of items can in the worst case take up to almost a minute.

From the outside it is hard to understand what takes so long here. PCI transfer speed towards the GPU can not be the limiting factor (we talk many seconds here … for a few GB at best) … if the “SSD - SATA - RAM - CPU postprocess - RAM - PCI transfer to GPU RAM” steps are the cause then I really would prefer the system to utilize way more GPU RAM as well as CPU RAM in order to cache as much of the “historic” (already pre-computed) data as possible.

The new slider from WU6 goes into that direction … but it clearly is not as “aggressive” as it could be.
Right now I see (at most) a 25% RAM utilization … and I would love more RAM usage (when RAM is present).

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Ok thanks, yeah I’ve done that, just wondering if there was anything I else I could do to improve the visuals. If you can extend that beyond the in-game sliders, maybe there were other sneaky ones too!

I notice when I use the sim and check the Memory view in Task Manager the sum of Committed plus Cached is close to my available RAM, so all the RAM is used either by programs directly or as a cache. I think a discussion about RAM usage in MSFS is incomplete without also considering how much swapped virtual memory belonging to MSFS is cached to RAM and how that affects MSFS performance.

I do not know how to measure that though. Any ideas?

@KillerJackson82 I considered page file. I had initially set it larger than recommended as I had a lot of SSD capacity, but since upgrading the RAM I’ve had it set to the recommended settings, 4 or 8GB I think.

I think I tried turning it off to use more RAM but from memory I don’t think it made much difference. The consensus seems to be that turning it off completely is not a good idea.