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Hi.I'm experiencing some very odd framerate problems, and after doing a search, it appears I'm not the only one. In fact, it's so widespread that I think it may be a bug in FS2004.Try this experiment and see what you get, it doesn't take long:First, set your display settings like this:Everything at max detail, including autogen. Set resolution and FSAA/AF settings to what you usually play the sim at. Set target framerate to unlimited.AI aircraft density should also be at full.1. Start a flight from Portland-Troutdale (KTTD). Default 172 Skyhawk, Summer, Day, Fair Weather theme.Start on runway 07. When the flight starts, switch to 2D panel view, then press W twice (to remove the panel). Zoom out to 0.5. Note the framerate.2. Now, activate slew, and move yourself to just above Portland International airport, at about 2000 ft., then turn so you have Portland-Troutdale in view. Wait for textures to reload. Note the framerate again.Now try it with these display settings:-Everything LOW, except Autogen at the highest setting.-and finally, set Autogen to the lowest setting too (none).When at #2 (over Portland Int. with KTTD in view) I get the following framerates:Everything at max: 6.8 FPSEverything at LOW except autogen: 20 FPSEverything at LOW including Autogen: 75 FPSThis does not just happen here, I've experienced it at many other places including SEATAC, somewhere between Tampa and Lakeland, Half Moon Bay, etc. etc.However, at many places, it does not happen. It does not seem to be related to scenery complexity. Sometimes it happens even at simple, less detailed airports, and sometimes the FPS is great at complex airports. It doesn't seem to be related to cloud visuals either. If I select the Clear weather theme, I still get low framerate at certain places.Please, try it out and post your results.

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Interesting. Same results here. I've been playing with the autogen-is-the-problem theory for a couple of weeks now but still haven't been able to pin down a proximate cause. Anyway, I ran the experiment twice as I have Ultimate Traffic and some non-standard cloud textures installed and I wanted to eliminate the effect of those. Doesn't matter though, the incredible framerate hit from the autogen is there in either case. More tests to run....With weather and AI on:Everything at max: 9.8 FPSEverything at LOW except autogen: 25.6 FPSEverything at LOW including Autogen: 80.3 FPSWith weather and AI off:Everything at max: 14.1 FPSEverything at LOW except autogen: 30.1 FPSEverything at LOW including Autogen: 134.3 FPSDougNorthwood 2.2a at 2.508Ghz (Intel HSF)Abit TH7II-R512MB Samsung 40ns PC800ATI 9800 Pro (128MB)Cat. 3.6's DX9b WinXP ProWD's 20GB, 20GB, 60GB, 120GB, 120GBInwin case / Enermax 431W PSU

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Interesting. The thing is that the Autogen shouldn't cause such a HUGE FPS hit. Sure, it may slow down things a little, but nothing like this. Also, at more complex and more populated areas, the framerate is actually OK, even with autogen at max and at some less complex areas it's incredibly low.I see that you're running an Intel system, so it's not a AMD-only problem.Can anyone with a Geforce try this and see what you get?

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I'm not sure why anyone would think autogen would NOT cause a framerate reduction.Autogen are textures mapped to polygons. Some autogen buildings and objects are actual library objects, some are closely related to "Advanced Buildings", and other, like bushes and trees, are simpler models, but still textures mapped to polys.Anytime you have a large number of polys, whether from a few complex objects, or many simple objects, you will have a load on the computer system.This is not a bug. If you don't want the object-associated framerate reductions, turn down the autogen, the scenery complexity, and the ATC. And watch which addons you apply to the sim. It's just simple math.Irregardless of how the sim "releases" polys and textures from memory, ALL objects can slow the sim... and it will be most noticable with systems with slow CPUs, slow GPUs, slow motherboards, slow memory, low system memory, low graphic card memory, or systems that have other background tasks running. Operating systems may also influence this as Windows98 and ME are most probably not the most efficient of systems.There really is nothing to investigate or study here... it's just common sense. Even the most up-to-date hardware will not run FS2004 to it's maximum. I still use CFS2 after 2 major hardware upgrades, and I now get a 10X increase in FPS due to more-faster hardware. The point? This is not a new problem. Dick

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Dick - I'd agree except for two points - the FPS hit is not consistent and it's far too big for the amount of polys involved. How many polys does it take to make a 100+FPS drop on a 2.5Ghz box running a 9800 Pro? I don't know either, but, for sure, it's more than that needed by the simplistic boxes and trees that MS calls autogen. What got me looking at the issue in the first place is the situation where a framerate of, say, 30 will suddenly, and without apparent reason, drop to 10. And, then, by simply moving the autogen slider down one notch and then back again, the framerate jumps right back up to 30. That has nothing to do with computing polys as the number is the same in both cases. Too many people with knowledge and judgement I trust are reporting similar findings. If it were just a aimple matter of CPU horsepower none of us would have bothered in the first place. No, there is, indeed, a new problem of some sort. It's just a matter of finding the cause(s). Doug

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I would agree with Dick. A performance hit is to be expected since you're adding more work for the computer to do.HOWEVER, the framerate reduction is NOT consistent - it only happens at certain places. The problem we're investigating is not "Turning on Autogen causes a performance hit". This is hardly a surprise that it does.The problem is more like "Turning on Autogen causes a HUGE performance hit at CERTAIN locations" within FS. Also, it can happen over simple, rural areas with very little scenery. Sometimes you may get 10 FPS out at a rural strip in the middle of nowhere, and 25 FPS over a major city. I'm not even sure Autogen is the real problem here. A contributing factor, for sure, but maybe not the root cause of the low framerate?Also, it doesn't matter if you're flying through multiple cloud layers with rain and haze effect or you're using the Clear Weather theme, the clouds do not add to this extreme performance hit. Doesn't make sense.You may be flying along at 30 FPS and suddenly the FPS tanks and goes down to 10 or less, with NO change in scenery complexity. For example, I was on base for some airport (don't remember, which. About 50 miles south of Portland), and the FPS was at about 9. As I turned final, it jumped up to 24 FPS (locked at 24) again. There was nothing special in view on base that would cause this huge performance hit. Also, if you followed the steps I provided in the initial post, you would have noticed that as you point the plane towards Portlant Intl., a fairly complex airport, the framerate is OK, but when you swing the view back towards KTTD, a smaller GA airport, the FPS goes below 10! That is NOT right.Microsoft has an email address to contact the FS team at tell_fs@microsoft.com. However, only send an email if you feel you have something useful to say. Sending "flames" or abusing the service won't accomplish anything :)

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I have to admit that after getting my 9800 I have seen the same thing. Running a P4 with 512mb ram and medium sliders, I see the same strange thing. The sudden dip in frame rate is not the HD, no activity there. It happens at random times too and its not predictable with autogen settings and scenry complexity at all. Its funny but I was at Portland troutdale last night testing this very same thing. I thought it looked like a nice little airport!! :) I am by no means pushing my radeon's capabilities either. Im running in 1152 res, 32 bit and only 2X FSAA and conservative Aniso settings.I thought I had this problem licked after going to the Radeon 9800(from a GF4 Ti4200) but its apparently still here. Another hint that its a memory or FS related issue is that if I go back to default settings for terrain ext radius and default radius the stuttering will just about totally dissappear. It seems with more textures the problem is much more noticeable. I have a large fixed swapfile and even if I let windows manage it it still happens. There is NO HD activity during these frame rate drops. What I see is a constant 24 fps at most locations, but after flying for a few minutes I will get these momentary drops, just a sec or so, maybe less, with a frame rate that goes from 24 or so down to about 14 or so, then right back up. Mine does not stay at the lower numbers. It seems to be triggered by not necessarily the autogen but possible the scenery bgl's or the distance from certain things like airports and other objects. The really strange part is its almost impossible to repeat with any consistency. Ive benched my system and have NOTHING running while doing FS. All other sims/games dont do anything like this. Im convinced its some kind of legitimate bug. Ive seen enough posts about this or something similar to think it warrants looking at. Hornit

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I have tried using the default FS9.cfg file and the problem is still there. Maybe a bit less severe, but still there, for sure.

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Hi Hornit, Did you try to disable all shadows in fs9.0 ? I had this problem before, but now it never happend again, I run fs9.0 all to slider right. Target framerate to unlimited, is not a good idea, try to lock your scenery to 25 or 30, your scenery will update the terrain faster. Try to disable the anasotropy and test everything, decrease the autogen little, water animation/reflection."I will get these momentary drops, just a sec or so, maybe less, with a frame rate that goes from 24 or so down to about 14 or so, then right back up. Mine does not stay at the lower numbers."Even not a second, but lower than a half of second in my case, not noticable for stutter or when your frame rate display is not activated. "Target framerate to unlimited"Why ? Never"Set resolution and FSAA/AF settings to what you usually play the sim "VERY VERY important on system capacity and configuration"The really strange part is its almost impossible to repeat with any consistency"It really depend where you fly, how dense is the area and how many details are below included autogen.The result will be different on lower, mid and high system, I don't think it's a bugs but, a more power system needed here. Every Microsoft release always push the software for later system spec. P4 3.2 GHZ 800FSB, 1024 Ram, GFX-5800 128MB 8X EricBest

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"And, then, by simply moving the autogen slider down one notch and then back again, the framerate jumps right back up to 30. That has nothing to do with computing polys as the number is the same in both cases."This is a point I was trying to make. The number of polys does change when you refresh the scenery by altering the setting and reentering the sim. Anytime you see the "Terrain Loading" message, the scenery is refreshed.A refreshed scenery does not carry the "baggage" of your previous path. You have forced the sim to release that accumulation... and it starts collecting again immediately, and will not release the newly acquired polys and textures until you leave the area. Just fly to an area of little or no objects some distance away ( a forested area will do, as the tree autogen has very little load ), and your framerates will increase ( and the memory use will drop ) as the sim lets the baggage go.Scenery objects ( BGLs ) can be controlled by their header settings.It appears we have little control over the distance at which autogen is perceived by the sim, once it is displayed. This is an important distinction. The memory and CPU hit occurs as autogen first comes into the viewport, but seems to persist somewhat even after the autogen is no longer visible in the distance... apparently then retained until a maximum distance to the aircraft.Changing the view direction can reduce the CPU load, but doesn't have the same dramatic effect of refreshing the scenery. ( You can refresh the scenery by entering the Display menu, and just moving the terrain mesh setting down one notch. The autogen slider doesn't even need to be touched. ) Most major airfields are near areas of large suburban landclass, and that is the greatest FPS/CPU hit. As you near landing, the airport objects, lines, autogen telephone poles, shadows, lowering landing gear, and even the audio usage of the sim build up a huge hit on the CPU, Memory and Bus. Add to that the accumulated 'baggage' of the suburban autogen you just flew over, and the strain is too much. Pause and refresh the display, and the baggage is gone: the sim becomes landable.It's the only explanation I can invent.What we require is a method or CFG setting that will let the accumulated autogen objects release earlier... at a distance closer to which they are actually displayed.Another trick to reduce the FPS load quickly is to increase the zoom factor. This doesn't get rid of the "baggage", but restricts the actual number of objects in the current viewport, and so reduces that object/texture factor. ( Decreasing the zoom has the opposite effect ). I don't know if that would be a valid trick to use on landings to keep the sim stall-free or stutter-free, but might be worth a try.Dick

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Hmmm...Good point Dick. I'd never considered that the problem may be a baggage-in-the-buffer type of issue. I suppose that could be the case and never even show as inordinate memory useage depending on how the sim allocates the resources. If so, and if the only solution is via the bgl's and/or landclass files, we're probably not going to know until the SDK is released. Still doesn't explain the large instantaneous drops we're seeing though. More tests to do.....Doug

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That's the point! Autogen scenery should NOT accumulate to the point where the framerate drops to BELOW 10 FPS on a 2.5 GHz machine. If it does, something is clearly wrong, most likely with regards to how FS handles scenery and texture data. I have also tried using low-resolution replacement textures for Autogen, but the difference is only maybe 0.1 to 0.3 FPS. FPS still tanks at certain locations.Remember that the big surprise with FS2002, was the small performance hit of Autogen. Why would MS suddenly do something to completely ruin autogen rendering?Modern computers have at least 512MB memory (1 gig is not uncommon) and a 128 MB or even 256MB videocard.I have monitored memory usage while running FS2004, and the memory load does not increase significantly over the areas with low framerate. It's pretty high at around 480 MB, but there's no significant harddrive thrashing or swapping going on and the memory load is pretty constant.There is an unrelated memory-leak problem, but it was discovered to be caused by incorrect installation of landclass files. So, RAM can not be the problem here.This leaves the issue of videocard memory, and this is where I think something is wrong, allthough I'm not certain (I didn't program FS2004, after all ;) ). It's likely that FS2004 leaves too many textures loaded into the local videocard memory, forcing new textures to be loaded over the AGP bus. If that is the case, users of 256MB videocards should not experience this signficant loss of performance. But what is also odd is that users who have replaced the autogen textures with low-resolution replacement textures should not experience the same loss of performance, but that's clearly not the case. Maybe it leaves unneeded polygon data on the card?Also, your theory does not explain why SOME VERY COMPLEX scenery areas (I never experienced the slowdowns over Miami, for example) do NOT display this problem, while a rural field somewhere in OR would cause the framerate to drop to 8 FPS."Changing the view direction can reduce the CPU load, but doesn't have the same dramatic effect of refreshing the scenery."I'm afraid you're wrong. Sometimes, at least on my system, moving the view 90 degrees by looking out the side window, makes the framerate jump from 6 FPS up to 30, even if the scenery is equally complex. Looking straight forward again returns the FPS to slideshow-mode. It's like there's something invisible placed out randomly throughout the world, that when it comes into view slows everything down to a halt.Also, look at the "other" thread about this issue, titled:"PROBLEM: Autogen rendering is major FPS hog!""We are dealing with a major problem here, and denying that it exists will only make it take longer to resolve it.

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You are correct in your theories, it's just that in this case, I think we're dealing with some, at this time, unknown factor. A bug, a conflict of some kind. Normal rules don't apply here. I will be compiling what I know so far about this issue and forward it to Microsoft. I suggest everyone does. They have a much greater chance of discovering what the problem is since they developed the sim :)Here are two screenshots to show my point.Don't you think these numbers are just a tiny bit "wrong"? The first shot is over Miami International. The other two are over the Portland OR area. Don't you think that it's a bit strange that the framerate over Miami is almost twice as high on average, as the framerate over Portland OR? What videocard are you using? Have you tried reproducing this by following the steps in the initial post of this thread? Especially if you have a Geforce, or a 256MB videocard, I would appreciate your results.http://forums.avsim.net/user_files/32788.jpghttp://forums.avsim.net/user_files/32790.jpghttp://forums.avsim.net/user_files/32791.jpg

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>Here are two screenshots to show my point.>>Don't you think these numbers are just a tiny bit "wrong"? The>first shot is over Miami International. The other two are over>the Portland OR area. Don't you think that it's a bit strange>that the framerate over Miami is almost twice as high on>average, as the framerate over Portland OR?Not at all, as this is an Apples to Oranges comparison...Miami is a rather flat area with a sparse variation of landclass compared to the CPU gulping Mesh of Portland as well as more variation of landclass, which also will gulp down more CPU resources via the additional AG objects loaded as a result.Mesh is a real FPS killer for a number of reasons, obviously all of the mesh/triagles have to be calculated and rendered as you move and on top of that all of the shadding and shadow rendering will continue to load the CPU as well as video card.Simply lowering "Mesh detail" to 92-87% can give you a performance boost equal to a decent CPU upgrade: From FS8 via LasVegas sceneryhttp://www.frontiernet.net/~pleatzaw/reviews/GF3%20vs3.gif

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-"But what is also odd is that users who have replaced the autogen textures with low-resolution replacement textures should not experience the same loss of performance, but that's clearly not the case.-"You should take a look in your FSim SceneryGenerictexture folder, there are additional autogen textures that may have an affect. They range in resolution up to 1024x1024.Kurt M

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No, the mesh isn't the problem.Some areas like Miami work well. Not great at 16-20 FPS but that's normal because of the complexity of the scenery.Tampa, which is also pretty flat, however, turns the sim into a slideshow. Tampa and Miami have a fairly similar landclass, they're both flat areas, yet the framerate over Miami Intl. is twice that of the framerate over Tampa.I have found that Hawaii works without slowdowns, even with an addon mesh, and it's a very computing intensive area.The slowdowns are pretty randomly scattered, but they always happen at the same places.This isn't about scenery being too complex for the computer, or people running excessively high detail settings. There's nothing special about the scenery at e.g. Portland to warrant this extreme loss of performance (below 10 FPS). This is almost certainly the result a bug or conflict causing severe loss of performance. That's why I'm trying to find out if it happens on all systems or only on systems with a certain configuration. From a thread at Flightsim.com, it appears that it happens to 9x as well as 2k/xp. It also seems to happen on both AMD and Intel systems. I haven't found out yet if it happens with both Geforce and Radeon cards. I would appreciate some results from users of Geforce cards (GF4 and GF-FX).(mesh at 100%)http://forums.avsim.net/user_files/32810.jpghttp://forums.avsim.net/user_files/32812.jpghttp://forums.avsim.net/user_files/32813.jpg

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Hi JimmiG.Could you post some saved example flights as a zipped file attachment?That would allow viewers of these posts to try them on their systems. with different settings.The "My Flights" are stored in a folder similar to this:C:Documents and SettingsDick.LUDOWRMy DocumentsFlight Simulator FilesIf you have My Documents on the desktop, it they will be in the "Flight Simulator Files" folder. Just include the *.flt and *.wx of some problem flights and a couple of non-problem flights, and a text file of your settings and results and expectations. That way we'll all be seeing something that's similar, and we'll see if this is a system/hardware issue or a fault of the sim.Dick

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