Multi-threading for CPUs?

[Spidey002]

Something I haven't seen mentioned yet is multi-threading capability for CPUs. Will this be part of the new engine? 
This would be great to have on our modern CPU architecture instead of needing CPUs that have high single-core capabilities.

[YoYo]

Good question, MT should be obligatory, what also about DLSS 3.5+?

[Aapje]

Multithreading should already be better thanks to the switch to DirectX 12, which is more multithreaded than DX 11.

[w00dy]

I'm hoping multithreading will be better in this game, I currently have a 7900x and feel it is under used when playing BOX.

[LuftManu]

Even if I am not an expert, having DX12 opens the possibilty to have much better optimization and work for CPU.

[Aapje]

Yes, but that is just for the rendering. Doing the game calculations in a (more) multi threaded way is independent of DirectX.

[Panzerlang]

Has to be a no-brainer, surely!

[Tomsk]

This is my biggest question as well. One of the biggest issues with IL-2 is that it is single threaded. This makes it hard to run complex missions with many aircraft at high frame rate. Moving to multi-threaded rendering & DX12 would help with the rendering side, but if the simulation is still fundamentally single-threaded I expect it will continue to struggle. Especially since the developers dream for IL2-Korea seems to be having large flights with many aircraft; this is likely to be even more CPU heavy than IL2 GB.

[1PL-Husar-1Esk]

Single threaded, who said it is ? Some parts of the game could be sperated then sync before presented to user but it's not benefitial to all , net results might not be that great to effort put in.

[Aapje]

54 minutes ago, Tomsk said:

Especially since the developers dream for IL2-Korea seems to be having large flights with many aircraft; this is likely to be even more CPU heavy than IL2 GB.

 

This is specifically for bombers, who get a simplified flight model, which reduces CPU load. So you are incorrect. They can increase the size of bomber formations because they will lower the CPU usage.

[MajorMagee]

It would be nice to know what the minimum hardware requirements are going to be.

[Tomsk]

4 hours ago, 1PL-Husar-1Esk said:

Single threaded, who said it is ? Some parts of the game could be sperated then sync before presented to user but it's not benefitial to all , net results might not be that great to effort put in.

 

IL-2 is quite obviously effectively limited to a single core today. The game is also CPU rather than GPU limited for most people; fps problems are common and they are almost always due to the CPU being overloaded. Moving to a more multi-threaded model would allow the game to offload CPU heavy work (such as flight models, AI, etc) to other cores and prevent the rendering being so badly affected by things like having lots of units in the mission.

 

4 hours ago, Aapje said:

 

This is specifically for bombers, who get a simplified flight model, which reduces CPU load. So you are incorrect. They can increase the size of bomber formations because they will lower the CPU usage.

 

Simplifying the flight model for bombers could also reduce CPU load. However, the point stands: more is more. Having the game effectively make use of multiple cores would allow bigger missions, more sophisticated flight models, better AI and busier multiplayer environments. IL-2 is very CPU limited today and has fps problems because of it (especially for those of us that fly in VR), moving to a multi-threaded implementation could help a lot. Speaking as a software engineer increasing the use of multi-threading is the obvious way to improve this.

Edited July 22, 2024 by Tomsk

[=MERCS=JenkemJunkie]

I haven't seen them say anything about increasing CPU utilization, but lots on increasing optimization. Obviously increasing both is the ideal, but the BoX engine is tied down by so many anchors that cutting those anchors away alone could be a giant leap. Well just have to wait and see if the optimizations get CPU performance into a good enough state.

[Aapje]

All sims tend to get CPU bound relatively soon. That just seems to be a consequence of the kind of software you need for simming.

 

Multithreading might be useful, but it is not something magical that makes everything faster. In only works in some situations and not in others. It's very hard to say if and how much it would help for the flight models, AI, etc.

 

Quote

The game is also CPU rather than GPU limited for most people

 

That is in part a consequence of the game not being that graphically demanding and being designed for fairly weak GPU's. Most likely, the new engine will have graphics options that will tax the GPU a lot more.

[LukeFF]

5 hours ago, MajorMagee said:

It would be nice to know what the minimum hardware requirements are going to be.

 

We're still a long ways away from being able to publish that. 

[Tomsk]

On 7/22/2024 at 7:55 AM, Aapje said:

All sims tend to get CPU bound relatively soon. That just seems to be a consequence of the kind of software you need for simming.

 

Multithreading might be useful, but it is not something magical that makes everything faster. In only works in some situations and not in others. It's very hard to say if and how much it would help for the flight models, AI, etc.

 

 

That is in part a consequence of the game not being that graphically demanding and being designed for fairly weak GPU's. Most likely, the new engine will have graphics options that will tax the GPU a lot more.

 

I think it's largely just a consequence of the IL-2 engine being quite old. DCS recently added multi-threaded to their sim and it improved performance very significantly, especially in busy missions. Also as a software engineer specialising in parallel algorithms, and quite a lot of experience in game and simulation development, I don't see any particular reason it couldn't benefit from parallelisation. As I say, DCS is solving a similar problem and has seen significant gains.

 

It's important to remember the goal is not to tax the GPU more. The goals are more like being able to get good fps, good graphical quality, high quality simulation and be able to support large battles with lots of units. IL-2 doesn't entirely succeed at those goals right now, primarily because it is CPU limited. If they took the same engine for IL-2 Korea, and simply upped the graphical requirements without improving the CPU bottlenecking, then it would struggle even more than IL-2 does. Sure it might then be more "GPU limited", but only because it's running worse overall.

[Panzerlang]

Bearing in mind that a lot of DCS'ers (me included) are using a program called 'Lasso' to regulate the use of P and E cores (with mixed results). Regardless, I still think Korea needs to go MT.

[LukeFF]

Well, now's the time to ask about that: 🙂 https://forum.il2sturmovik.com/topic/88994-questions-now-being-taken-for-the-next-brief-room-episode/

[=621=Samikatz]

4 hours ago, LukeFF said:

Well, now's the time to ask about that: 🙂 https://forum.il2sturmovik.com/topic/88994-questions-now-being-taken-for-the-next-brief-room-episode/

 

What does "game world display system" mean?

[LukeFF]

8 hours ago, =621=Samikatz said:

What does "game world display system" mean?

 

Visuals, graphics rendering improvements, etc.

[Spidey002]

On 7/23/2024 at 11:59 AM, LukeFF said:

Well, now's the time to ask about that: 🙂 https://forum.il2sturmovik.com/topic/88994-questions-now-being-taken-for-the-next-brief-room-episode/

Coming back to this in 2025, I can’t remember if the original question I had got answered: Will there be multithreading?

[LukeFF]

Yes, it was talked about a few video episodes ago. I believe the internal builds are running five threads right now. 

[YoYo]

Why not all?

[AndyJWest]

6 hours ago, YoYo said:

Why not all?

 

Because the law of diminishing returns sets in pretty quick when trying to multithread something as inherently non-parallelizable as a combat flight sim. Adding the extra code necessary to split off work to a further thread can easily end up making everything run slower.

 

And what would 'all' mean, anyway? They are building the application to work on a broad range of hardware.

[AEthelraedUnraed]

5 hours ago, YoYo said:

Why not all?

All what? "All threads"? There is no such thing as a maximum amount of threads, so there isn't such thing as "all threads" either. You can run a million threads if you want, although as AndyJWest explained, your PC will grind to a halt.

 

23 hours ago, LukeFF said:

Yes, it was talked about a few video episodes ago. I believe the internal builds are running five threads right now. 

I find that very hard to believe since IL2 already has a large multitude of that amount of threads. Doing a quick count, IL2.exe runs more than 120 threads. Perhaps the engineers meant the AI or physics or something similar are now running on 5 threads?

[LukeFF]

Like I said, it's discussed in one of the videos with one of our programmers. 🙂 Perhaps there was a misunderstanding in the translation. 

[jollyjack]

On 7/23/2024 at 12:47 AM, Panzerlang said:

Bearing in mind that a lot of DCS'ers (me included) are using a program called 'Lasso' to regulate the use of P and E cores (with mixed results). Regardless, I still think Korea needs to go MT.

 

A PS, and now 2025 LoL: ProjectLasso ... is it any use for IL2?

Bought it for DCS for the stutters, limiting core afinities, but found a work around for that now to deactivate affiniy for all E cores only.

[Panzerlang]

On 1/10/2025 at 4:56 AM, jollyjack said:

 

A PS, and now 2025 LoL: ProjectLasso ... is it any use for IL2?

Bought it for DCS for the stutters, limiting core afinities, but found a work around for that now to deactivate affiniy for all E cores only.

I have hyperthreading disabled in the BIOS. Imagine my suprise when I reinstalled Lasso, fired it up and "coo, I have only eight physical cores now!" Lol.

Anyway, I have all the E-Cores disabled for IL2 and the physical cores tweaked. IL2 runs sweet as a nut currently.  Lot of other tweaks that I did for DCS are most likely helping IL2 also of course.