Stutters

[a320driver]

Have an on going problem with this scenery. Whenever I am near JFK, I get constant stutters. By constant I mean every time I change views or pan the cockpit. This also happens in flight as I approach. Short little stops and starts that got me into trouble the other day on short final. The stutters were such that I could not maintain a constant approach. Any ideas?

Thanks in advance,
Joe

[virtuali]

Since this is the first time someone reported this problems, it's probably something related to your configuration, which of course it's not possible to diagnose, if you don't say anything about it.

By configuration, it means hardare, but also other addons you are using because, for example, if you are using it with an airplane that takes alone 2/3 of your system ram just for itself, there wil be not much left for the scenery to run so, stutters will be normal.

[Michael McE]

Since this is the first time someone reported this problems, it's probably something related to your configuration, which of course it's not possible to diagnose, if you don't say anything about it.

By configuration, it means hardare, but also other addons you are using because, for example, if you are using it with an airplane that takes alone 2/3 of your system ram just for itself, there wil be not much left for the scenery to run so, stutters will be normal.

I have experienced this as well - ever since first install.  I did not bother to report it because it is not a problem unique to FSDT KJFK.  As Umberto pointed out, it really has to do with a lot of interacting variables, texture loading, cpu, gpu, etc., etc. and so on. 

There are many, many posts all over the FS9/FSX forums about dealing with the problem.  In my case it remains unsolved.  At some point I'd rather fly and enjoy what I have then to constantly tweak and get no return on my time investment.

-michael

[a320driver]

Since you mentioned system specs, here they are:
Intel Core 2 X6800
Asus P5N32-SLI Premium
2GB DDR2 Corsair Dominator XMS2 @ 1066 MHz
2x SLI Quad Nvidia Geforce 7950GX2 1GB
2 Western Digital Raptor 150GB (10K RPM) in a Raid 0 Stripe
Topower 1100W

I get this issue with whatever I fly, from the simplest aircraft to the most complex. I know this problem has been discussed in many other places, have read many of those discussions. However you never know when you might find the one person that has the answer....they might just be lurking somewhere around here!!

Regards,
Joe

[virtuali]

I'm not asked only about system specs, but what other software you are running. Addon aircraft was just an example, but everything counts: terrain, AI packages, etc. Everything contributes to a specific resource footprint in a specific place.

Also, it should be interesting to know if your stutters are constant, or they only happen when JFK is loaded (about 8 nm from the center of the airport) and they eventually settle down after a few seconds.

Also, when you see stutters, do you notice some kind of hard disk activity ?

Are you running FS9 on that system ? I'm assuming yes, since you posted it in the FS9 section.

If yes, I'd say you are running the wrong system for FS9, because it doesn't support dual-core at al. The only benefit from a dual-core in FS9 would be when using many *external* addons, by external I mean external .EXE files, not airplanes with gauges or any kind of scenery addons.

Stutters are in general created when a very complex scenery is loaded all at the same time. Since FS9 doesn't have any kind of dual core support, opposed to FSX (which can use 100% of both cores when *loading* the scenery), the load process of scenery+texture might stall the sim for a moment, causing the stutter.

Also, there's the added complexity of using a SLI config, both because FS9 doesn't really support it (and not even FSX) except for the ability to drive bigger screens without too much fps loss, but still the video driver has to do more work, because textures needs to be sent to both GPUs.

Another reason for stuttering might be caused by the sharing of IRQs (which IS possible, but it's not ideal) between some hardware components. The most critial ones are the IDE disks and the audio card, if they share the same IRQ, this might be a source of problems.

Also, there are some diminishing returns when using FS9 on a relatively powerful machine like yours: it's not as simple as using an FSX machine and getting magical performances from FS9, because FS9 is not suited to exploit the better hardware, so it would easy run into bottlenecks, because it hasn't really tought to handle such complex sceneries that weren't thinkable when it was designed.

In a word: FS9 do not "scale well", something that FSX does better. This means, FSX might run like crap on lesser hardware, but it runs better on the best hardware ESPECIALLY when the scenery (and with "scenery" I don't simply mean JFK, but the WHOLE picture around JFK, default scenery+city+terrain+AI+texture AND the airport addon) is very complex.

Do you have FSX ? Have you tried JFK in FSX, and see if if runs different/better/worse compared to FS9, as far as stuttering is involved ? Don't mind absolute fps (although I have similar fps in FS9 and FSX), but just notice the smoothness.

[Dimon]

The only benefit from a dual-core in FS9 would be when using many *external* addons, by external I mean external .EXE files, not airplanes with gauges or any kind of scenery addons.

The only benefit of dual-core in FS9 is that FS9 runs 3 times faster and smoother than on any single core system . So you guys, perhaps, overthink the issue a little bit. Too much complication to the simple thing.

As far as the topic concerned, I have also strange stuttering with strong 20FPS. I use such AI as AIA, DJC, EVAI, FMAI. All textures - DTX3 with alpha checked manually (I know I'm crazy, but I did that).

I stongly believe that stuttering relates to the scenery itself, since I have a destop dedicated for the sim only, I have clean system with many services turn-off. KORD doesn't have such issues and run nicely.

[Dimon]

Do you have FSX ? Have you tried JFK in FSX, and see if if runs different/better/worse compared to FS9, as far as stuttering is involved ? Don't mind absolute fps (although I have similar fps in FS9 and FSX), but just notice the smoothness.

Sounds like paid advertising...No, we don't have FSX and we do not plan to move into FSX until the following requirements will be met.

1) 10-12 quality scenery products; FSX-dedicated, not just FS9-converted
2) At least one quality plane designed for FSX only (I assume it might be LDS757)
3) Performance at the plank 35-40% higher than we presently have with current most expensive systems (I hope i7 might be an answer).

Hence...Late Fall 2009 - may be the majority of hard-core simmere will switch, if global crisis won't kill buying power of customers in US and Europe ( I guess they contribute 90% of your profits)

[virtuali]

Sounds like paid advertising...

? I was just ASKING if he had any chance to try the scenery on FSX and if he saw any differences.

No, we don't have FSX and we do not plan to move into FSX until the following requirements will be met.

All your requirements are start to come, one by one:

1) 10-12 quality scenery products; FSX-dedicated, not just FS9-converted

We'll have 4 sceneries very soon (5 in 3 months at maximum), and we are just a one developer, our FS9 sceneries are, in fact, FSX conversions...

2) At least one quality plane designed for FSX only (I assume it might be LDS757)

So, this will eventually come up. However, it's as usual wrong to consider only airliners as being "proper" planes. There are several quality planes already available for FSX, not necessarily being airliners, aviation it's simply much more than such a restricted view. I'd say we did a fairly well received FSX-only military airplane last year...but there are others already.

3) Performance at the plank 35-40% higher than we presently have with current most expensive systems (I hope i7 might be an answer).

Yes, i7 might be the answer. However, I'm perfectly happy how FSX runs on my 2.5 years old C2D E6700, because I don't not feel diminshed by having to put *some* sliders not at full right, since what I SEE it's already far better than FS9, and what I GET, in terms of capabilities is VASTLY better, without the need to wait for a new machine.

Hence...Late Fall 2009 - may be the majority of hard-core simmere will switch, if global crisis won't kill buying power of customers in US and Europe ( I guess they contribute 90% of your profits)

Sorry, but as our current downloads figures shows, the "majority" of hard-core simmers has ALREADY switched, because, in the year we are selling sceneries directly (so we can evaluate much better actual sales numbers and downloads stats), we started from a 65/35 advantadge for FS9 when we released Zurich, to a basically 50/50 when O'Hare came out, to a 60/40 advantage for FSX when JFK has been released.

EVERY other developer is just noticing the same thing, believe me, I just returned from a convention were I've met many other developers, and they all agree about this, it's happening. 

Those who still haven't switched, are now a minority of the hard-core simmers (which are themselves a *tiny* minority of all users), and considering we have another Christmas in between, with a new generation of CPU that has just been released, many more will switch very soon.

So, apart for the whole YAPD-eness of the post, which unnecessarily steered towards another pointeless FSX bashing, which was really uncalled for, considering that I've only ASKED the user if he had any chance to try JFK on FSX and nothing else was implied, if everything goes according to the plan, since we usually take an amount of time for making a big scenery like JFK, which is 4-5 months at minimum, we can't WAIT for the transition to start, but we need to be ready for it in advance, after KLAS is released, in the 1st quarter of 2009, we'll probably need to reconsider again our support for FS9, which is even more that we initially promised.

[virtuali]

The only benefit of dual-core in FS9 is that FS9 runs 3 times faster and smoother than on any single core system

It would be nice that using an unsupported Dual Core system in FS9 would auto-magically get a 3 times speed increase. It's not like that, the benefits you are getting, are just because of the greater efficency of the CPU architecture of the Core Due compared to the previous generation. With FSX you get it as well, but you get Dual Core suppor on TOP OF THAT, which FS9 doesn't have.

So you guys, perhaps, overthink the issue a little bit. Too much complication to the simple thing.

It's not simple, and oversimplyfing for the sake of it, doesn't help understanding the problem. Computer performances are not linear as you would like to suggest. It's more having a limited amout of resources that can be used up to a certain limit, and after that you have a drastic drop. But the opposite is also true: if a software can run ok on a certain machine, it's not certain it will KEEP increasing performances by keep adding hardware, because it only depends if the software is programmed to  exploit it.

The term "scales well" it's a very well known problem in IT tecnhology ( I haven't invented it for sure... ), and FSX DOES scales better than FS9. Which means, UP to a certain hardware available, FS9 is better, but there's a point when adding additional hardware starts to benefit FSX more than FS9, eventually to the point were FSX runs better.

As far as the topic concerned, I have also strange stuttering with strong 20FPS. I use such AI as AIA, DJC, EVAI, FMAI. All textures - DTX3 with alpha checked manually (I know I'm crazy, but I did that).

I have similar or better fps with FSX, and don't have any stuttering.

I stongly believe that stuttering relates to the scenery itself, since I have a destop dedicated for the sim only, I have clean system with many services turn-off. KORD doesn't have such issues and run nicely.

Yes, it might be. But it's NEVER the scenery "itself", it's always the combination of things you run together with it because, as I've said before, you are trying to force FS9 into something it hasn't been designed, without having the software support needed, and multi-core usage is the most striking one.

As we said, many times, our FS9 sceneries are not developed with FS9 in mind. The FS9 version is just a by-product of the FSX one. It might very well be that the scenery is simply not suited for FS9 as it has been thought, because every design choice we did, has been made keeping in mind how FSX works, sometimes this is good for FS9, because we put extra optimizations that helps anyway, but this is not guaranteed to be always happening.

Stutters ARE something that can be caused by the lack of multi-core support in FS9, because they are usually caused by texture loading, and texture loading IS the most significant use of multi-core in FSX, and this can be easily verified, because the maximum CPU usage on both cores can be usually seen only when the scenery is loading, but the multi-threaded handling is always happening in the background (cause texture are constantly moved in/out), and this helps keeping the stuttering problem away in FSX.

[Dimon]

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if everything goes according to the plan, since we usually take an amount of time for making a big scenery like JFK, which is 4-5 months at minimum, we can't WAIT for the transition to start, but we need to be ready for it in advance, after KLAS is released, in the 1st quarter of 2009, we'll probably need to reconsider again our support for FS9, which is even more that we initially promised.
What do you mean by "reconsider again our support"? Will you cut it down to signle FSX platform or instead, continue to work with dual-platform agenda?

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have similar or better fps with FSX, and don't have any stuttering.
No, no, no.... It's not fair. I mean 20FPS from PMDG747 VC with custom-made 170AI around, ASV, FE, GE PRo, UT USA. Such level of performance with comparable software is UNREACHABLE in FSX with modern day hardware and you know that very well.

[a320driver]

WOW....Took some time to do some testing, and when I come back I find this rather involved debate!!! I had FSX on my system and removed it. Could not get it to do ANYTHING I wanted it to do. At some point I am sure I will have to put it back and try again. Until then I will try to get FS9 to give me all it's got. I run WOAI, FS Genesis, Active Sky6. I also use a program to shut down un-needed programs during FS9 usage. I find the stutters the worst @ JFK. I do see some "micro" stutters at other airports. I also wonder about how sound might play a role, as the sound "jumps" many times when I see the stutters. I know this is a very complex issue, one that may never be rectified for FS9. In the meantime I will keep tweaking and.....someday try FSX again.

Regards,
Joe

[virtuali]

What do you mean by "reconsider again our support"? Will you cut it down to signle FSX platform or instead, continue to work with dual-platform agenda?

What we said since the beginning: every xxx months, we evaluate the market, and decide if it worth continuing support for FS9. Last promise was that we would have supported FS9 until the end of 2008, but since KLAS will be for FS9 as well, we are going to exceed it. Since you said yourself that Fall 2009 might be the final transition to FSX, we certainly can't wait up to then, but anticipate it at least 6 months so, after KLAS, another evaluation will take place.

No, no, no.... It's not fair. I mean 20FPS from PMDG747 VC with custom-made 170AI around, ASV, FE, GE PRo, UT USA. Such level of performance with comparable software is UNREACHABLE in FSX with modern day hardware and you know that very well.

GE Pro doesn't impact fps much, UT USA is not *absolutely* needed in FSX as it was in FS9 ,ASV makes a lot of independent background processing and it DOES benefit for Dual Core, and I get very good fps with a lots of AI, provided the right models are used.

So this leaves you with the old argument against FSX, which is how it runs with "that" 747...

As I've said, many times already, it's wrong to judge an entire platform because of a single problematic addon which impacts the fps considerably even in FS9. The LD767 is as featured as the PMDG, yet it runs *way* better on FSX. And the new Super80 from Flight One IS a very faithful representation of the real airplane and is a native FSX product which, of course, runs better than both.

So, it's not FSX, it's how the addons are made.

[virtuali]

I also wonder about how sound might play a role, as the sound "jumps" many times when I see the stutters.

You should have said this from the beginning!!!

I guess it somehow in my first reply to you:

Another reason for stuttering might be caused by the sharing of IRQs (which IS possible, but it's not ideal) between some hardware components. The most critial ones are the IDE disks and the audio card, if they share the same IRQ, this might be a source of problems.

But if you said that you hear sound jumping, that's beyond any doubt. Your audio driver probably has issues with IRQ sharing, there are even some parameters in the BIOS to control PCI sharing that might be tweaked to fix this. And, usually, a real sound card ( liek Soundblaster X-Fi this is what I use ) instead of the one that comes with the mainboard, might work better.

[a320driver]

I use a Soundblaster X-FI. I have the latest drivers for it. What are the Bios tweaks you speak of? I have been considering a different sound card altogether, as with this one there is constant poping and cracking.

Regards,
Joe

[virtuali]

It's usually called the PCI Latency.

There's also an utility to set it without going into the BIOS:

http://downloads.guru3d.com/download.php?det=951