Addressing Performance/FPS Issues

[Cameron]

Captains,

In the days since release of the Hot Start Challenger 650 there have been concerns that Gizmo and even the Challenger 650 plugins were causing a major performance impact. We went investigating this, and even got Laminar Research involved to understand what was happening under the hood of X-Plane to try and sort this out.

As it turns out, Gizmo is NOT the source of problems, and neither is the 650 plugin; not directly, anyhow. What's happening is somewhat complicated, but I'll do my best to be descriptive, yet brief.

X-Plane is programmed to use up all of your CPU cores in order to try and attain higher frame rates. In doing so, there's some major texture paging going on. The problem here is that it leaves almost no room for the Challenger to get its CPU operations done in the process, and mixed with a ton of texture paging, everything goes bust and tasks get stuck in a queue where X-Plane drastically slows down, things pause/stutter, and the experience becomes abysmal. If you happen to have your Plugin Manager open in X-Plane while this happens it will present itself as if Gizmo or the Challenger are using up an insane amount of performance, but this is actually just a mean trick when looking at it from a user perspective. X-Plane slows down so much that it LOOKS like our plugins are to blame as their tasks are not yet performed while X-Plane does other things. 

Before I go further, I should note, this is NOT applicable to everyone! Most customers here seem to have a great CPU/GPU combination that can handle all of this, but if you're one of the people on the struggling end of the spectrum, you'll want to keep reading this post!

Version 1.1.0 of the Challenger 650 introduces a new installer that has a selection for GPUs with more or less than 6GB so we can best optimize your install for you. This will help with some of the VRAM/texture paging operations.

That said, there's still more to the puzzle. Because X-Plane is using all the cores/threads on your CPU, it is not saving "room" for the Challenger 650 to do its operations efficiently and the CPU becomes oversubscribed. Laminar Research is likely to fix this issue for developers at a later date after X-Plane 12, so in the meantime we have a workaround to use that Laminar has sanctioned to give out to those affected.

 

If you are affected by this issue, please do the following (this is for Windows users, as the issue seems most prevalent with Vulkan):

1. First, find X-Plane's application and create a shortcut so that we can create parameters. Right click on X-Plane > New > Shortcut

2. Right-click on your shortcut, and select Properties on its contextual menu to open the shortcut's Properties window.

3. The shortcut's Properties window is the place where you can add command-line parameters for that shortcut. Select the Shortcut tab and look for the Target field.

4. You will see a place that has the path to X-Plane labelled Target. X-Plane's path will be in quotes. At the end of the quotes, make sure there is a space after the quotes, then type/paste: --num_workers=n  <== Replace the red 'n' with a number equal to three fewer processors/threads than your CPU has (this accounts for X-Plane's "main thread"). For example, if you have a 6 physical + 6 virtual processor CPU (known as Hyper-Threading for Intel and SMT for AMD) for a total of 12 threads ("logical processors" as Windows refers to them), you should put the number 9 in place of the red 'n'. Also be sure you have the TWO hyphens/dashes in front of "num_workers"!

5. You can now rename this shortcut to something like Challenger 650 if you like. That way you can just click this one when you know you'll be flying the Challenger.

If you are unsure how many processors/threads your CPU has, go into your About Computer setting and Google your CPU model number to find out. Be sure to use the total number with Hyper-Threading/SMT (if enabled) as your starting point!

We know this is a bit unorthodox, but we're doing our best to make whatever solutions we can for as many people as possible. Hopefully this makes your flying more enjoyable!

Edited September 3 by Pils

[Sunny0408]

After these parameters were added, all my planes had to be reactivated...

[Ben Russell]

13 minutes ago, Sunny0408 said:

After these parameters were added, all my planes had to be reactivated...

Correlation does not equal causation. 

These parameters have no affect on the x-aviation licensing system. 

[andresmado]

does this recommendations still apply?

[Pils]

1 hour ago, andresmado said:

does this recommendations still apply?

Yes.

[Cameron]

10 hours ago, andresmado said:

does this recommendations still apply?

X-Plane 12 will likely have a way for authors work through this. For X-Plane 11, this will always be a thing.

[Pils]

On 1/21/2022 at 4:54 PM, Cameron said:

--num_workers=n

I believe X-Plane doesn’t count its main thread in this value so that should be considered if necessary to free up additional processors for other uses, including an aircraft’s multi-threaded plugins.

[FarFoune59000]

Hello, 

even after applying these parameters. The brutal FPS drops (38/40  -> 7/5) are still present. It really hurts the experience with this beautiful plane.

I thought future updates would fix this problem...

Regards, 

[Pils]

15 minutes ago, FarFoune59000 said:

Hello, 

even after applying these parameters. The brutal FPS drops (38/40  -> 7/5) are still present. It really hurts the experience with this beautiful plane.

I thought future updates would fix this problem...

Regards, 

 

On 4/4/2022 at 9:23 AM, Cameron said:

X-Plane 12 will likely have a way for authors work through this. For X-Plane 11, this will always be a thing.

As Cameron says above, the only update that’s potentially going to help is X-Plane 12, and that’s still theoretical. (Unless you’re talking specifically about the FBO van.)

Edited July 5, 2022 by Pils

[notBillJames]

Hello. I currently run the latest version of the CL650. I had X-Plane installed on an old SSD that took a while to load, so I upgraded it to a new SSD that is faster. Both were connected to my computer via USB. After I switched drives, bad stuttering appeared in any plane that I flew. Looking in the plugin manager, each frame rate stutter is accompanied by a spike in Gizmo usage which led me to this thread. This is true in every plane, not just X-aviation planes. When I disable Gizmo, the problem goes away but then means I can't fly the Challenger or TBM. I tried the fix mentioned above to no avail as well, my target line is "E:\X-Plane 11\X-Plane.exe" --num_workers=14, and I run a i7 6900K which has 8 cores, 8 virtual cores. I'm not sure what else to try and I really love flying both of these planes. Any suggestions would be greatly appreciated and I am attaching my CL650 log below as well. 

CL650_Log.txt

[Ben Russell]

I am a aware of this issue. Thanks for reporting it. 

It has been fixed in the private developer version of gizmo. 

We are in the developer beta and bug fix phase. 

Hopefully the new version will be ready for public release soon. 

[notBillJames]

Hooray! I am so delighted to hear that I will look for an update. Does that mean the planes will have to be updated to work with the new version, or does gizmo update itself independently?

[Ben Russell]

Usually I'll release a zip file with install instructions for users that are feeling adventurous.

Sometimes X-Aviation will create a beta-gizmo installer.

Then when we're confident that it's ready for a wider release the new Gizmo build will be incorporated into the official product installers.

 

[Cameron]

6 hours ago, notBillJames said:

Does that mean the planes will have to be updated to work with the new version, or does gizmo update itself independently?

No, it's not like SASL where aircraft are version specific. All planes will work right away.

[notBillJames]

7 hours ago, Ben Russell said:

Usually I'll release a zip file with install instructions for users that are feeling adventurous.

Awesome, where should I look to find this zip file when you release it?

[notBillJames]

On 11/9/2022 at 3:35 AM, Ben Russell said:

Usually I'll release a zip file with install instructions for users that are feeling adventurous.

Hello Ben, I just wanted to follow up and see where I could find this once it becomes available. Really missing the challenger at the moment haha

[Ben Russell]

14 minutes ago, notBillJames said:

Hello Ben, I just wanted to follow up and see where I could find this once it becomes available. Really missing the challenger at the moment haha

There will be a post on the forum.

Click my username and find the "Follow member" button and you should get the appropriate notifications.

 

[notBillJames]

2 hours ago, Ben Russell said:

There will be a post on the forum.

Click my username and find the "Follow member" button and you should get the appropriate notifications.

 

Thank you!

[Martrenchard]

merci j ai applique la procedure pour (suivre le membre ) et obtenir la beta gizmo afin de recevoir les notifications  merci 

(vol cl 650 actuellement beta team)

merci beaucoup

Eric /// 

thank you I applied the procedure to (follow the member) and obtain the beta gizmo in order to receive notifications thank you

(flight cl 650 currently beta team)

Thanks 

Eric

[airforce2]

Now that v1.7 is out with XP12 compatibility, is the "--num_workers= n" command-line option still needed in XP12?

[Pils]

5 minutes ago, airforce2 said:

Now that v1.7 is out with XP12 compatibility, is the "--num_workers=n" command-line option still needed in XP12?

It is still relevant, yes. LR haven't made any significant changes that I know of.