Test: Setting CPU Affinity

Why don't you turn off one or two cores on your 8700K?

Most of DCS is still running in those same 2 threads. All the unit AI / flight models / collision detection / line of sight calcs etc are done on one thread. Anything they have done a major rewrite are split off the main thread. The problem is that a lot of stuff remains in this main thread. These threads, however, may jump from one core to another core so you'll see multiple cores being used. Some object loading and stuff may be done in parallel over all the cores though. Don't be fooled, DCS is still mostly the way it has been.

Why don't you turn off one or two cores on your 8700K?

Why would you? There is nothing to be gained. What little you save in power from disabling (idle) cores, is almost certainly offset by the fact you cant "use" those cores (or rather, that part of the die) to distribute the heat evenly across the entire die. That is why windows shuffles threads across cores. If you think about it, slightly lower hotspot temperature and thus potentially longer or higher boost clocks is not the best use imaginable for having 6 or 8 cores, but at least its better than no use at all :)

My DCS performance issues have been fixed!

I was pulling my hair out trying to improve my PCs performance in DCS Multiplayer. I changed to an NVME system drive, an DCS SSD drive, OCd my graphics card, but nothing helped.

Then I read this thread. I discovered through Task Manager that on my PC DCS.exe was only using one core, yet Steam VR was using all (I couldn't see the performance of one individual core, but was shown a CPU utilisation of around 33%). I set DCS to use two cores, and the sound stuttered. I set it to use all, and voila. Suddenly I had amazing performance. Before, I was averaging around 20fps (VR) or less, and now I'm averaging around 35fps, with it sitting on 40fps once I'm in the air. Suddenly flying in VR in MP was doable! I hope this helps someone else solve their PCs performance issues.

I discovered through Task Manager that on my PC DCS.exe was only using one core, yet Steam VR was using all

?

Do you mean core affinity for the process was set to only a single core? That doesnt happen by itself, that only happens when you configure it like that. Maybe you may have forgotten you ever did that or you did it inadvertently following someones instructions?

Does that CPU Affinity website know what cpu you have? Or is it just always displaying 8 cores and 16 threads for everyone?

http://store.tomandmiu.com/cal-cam.php

I have an i7 6700k. These cpus have 4 cores and 8 logical processors with hyper-threading?

So I am confused as to why that affinity website shows I have 8 cores and 16

Does that CPU Affinity website know what cpu you have? Or is it just always displaying 8 cores and 16 threads for everyone?

 

http://store.tomandmiu.com/cal-cam.php

 

I have an i7 6700k. These cpus have 4 cores and 8 logical processors with hyper-threading?

 

So I am confused as to why that affinity website shows I have 8 cores and 16

You click on the ones that are relevant to you and it outputs an affinity number - e.g I want to use the physical cores for my 4970k with HT so I click on 0 2 4 6 and the output is 85 (85 might be the best for your CPU too)

Does that CPU Affinity website know what cpu you have? Or is it just always displaying 8 cores and 16 threads for everyone?

 

http://store.tomandmiu.com/cal-cam.php

 

I have an i7 6700k. These cpus have 4 cores and 8 logical processors with hyper-threading?

 

So I am confused as to why that affinity website shows I have 8 cores and 16

It doesn't auto-detect. You click on the number of cores and it'll spit out the affinity mask to use.

This regedit fix for Windows 10 removed pretty much all stuttering for me:

I'm running a I9900KF@5Ghz and kept getting micro stutters all the time.

Did you turn off the power saving features in the Windows GUI? You want to make sure that you are not on "balanced" in the advanced power settings. You want to set it to "high performance".

Process Lasso works really well and it's much more convenient than regedits.

Stop promoting Project Lasso. You can set cores during DCS launch.

DO NOT USE AN EXTERNAL CORE SELECTOR, IT CAUSES INSTABILITY. Instead, create an autoexec.cfg file inside the Config folder in the Saved Games folder and use the command "affinity_mask = xx". Replace xx with number found using this website. http://store.fsxtimes.com/cal-cam.php

 

DCS runs best confined to 3 cores, with hyper-threading. Performance per selected cores will vary depending on CPU. I have a 6 core and use "828" so it is using cores 2, 3, and 5 including the HT thread for each.

autoexec.cfg

Stop promoting Project Lasso. You can set cores during DCS launch.

I'll promote whatever I think is good software, get over yourself, it's free donation ware. Your information is wrong about number of cores and hyperthreading. I've never had any stability issues with it.

I'll promote whatever I think is good software, get over yourself, it's free donation ware. Your information is wrong about number of cores and hyperthreading. I've never had any stability issues with it.

The only chipsets and corresponding CPU's that seem to benefit by setting core affinity are X99 and X299, maybe X79 too. If you like to do the math yourself, do it, ProcessLasso is the easy way.

Imho, for any Desktop Chipset/CPU later than Z170 it's not having any benefit. likely the contrary.

This horse has been beaten to death over and over on these forums and really, the only clear benefit were people with X99 chipsets if you read through this and other threads over the years.

The only chipsets and corresponding CPU's that seem to benefit by setting core affinity are X99 and X299, maybe X79 too. If you like to do the math yourself, do it, ProcessLasso is the easy way.

 

Imho, for any Desktop Chipset/CPU later than Z170 it's not having any benefit. likely the contrary.

 

This horse has been beaten to death over and over on these forums and really, the only clear benefit were people with X99 chipsets if you read through this and other threads over the years.

I have read through the thread. The guy I was quoting obviously didn't. I don't set core affinity in Windows or Process Lasso and never said anything about doing so. I set a 2 core ratio overclock in BIOS when playing DCS and then Windows and Process Lasso take care of the rest automatically. The guy I was quoting was putting out wrong information about hyperthreading, number of cores, and stability. And Process Lasso works very well for people who don't want to download autoexec.cfg files from random people in a forum.

This stuff is complex enough without confusing the issue for new players. In any given chip there will always be cores that can run faster. I have a top 20 score in the world on 3dMark using Process Lasso and am in the 99th percentile of scores on my current rig so I'll go with my own experience and the technical expertise of people who actually know what they are talking about over random people on a forum.

The fact remains that DCS does not use more than 2 cores and does not use hyperthreading. Other background and streaming programs might, but not DCS. Not yet anyway. That hasn't changed since this thread started.

People are more than capable of using their own judgment, but you need to have correct information to do that.

Snake,

I was not criticizing your statement, actually I wanted to 2nd yours :)

It is indeed a very complex matter and I don't look at myself as being fully aware of how cores and threads are handled in any OS, I am a general admin and no programmer with deep inside knowledge. My statement is based on systems I had myself in the last 4-5 years, 2600k, 6700k, 7700k and now 8700k and what other's with X99/5930k or similar HEDT systems stated. I can enable PL but I see no benefit on my end, it also doesnt lower performance either,

so for my 7700k and 8700k it made zero difference with HT on or off. I tested a few runs with less cores and saw no benefit either, heck, I had nothing to complain when I started those tests, they were out of curiosity for the matter itself.

I think we both agree mostly, if I am wrong, PM me..LoL

No worries, Bit. Apologies for coming off like a butt hole. I've just read so many posts and threads by people new to the hobby who get confused by this stuff and contradictory info.

If I ever actually have the time I want to start a YT channel that focuses on benchmarking flight sims since no one else has yet. The best I could come up with for DCS was the IA Free Flight on the Caucasus with the T-51/Su-25. But still so many variables, it's hard to establish a one size fits all baseline. I saw some people using a .trk for some tests, but that's not really valid due to playback issues and you are watching a prerecorded .trk and not playing in real time. Plus people could always fudge the numbers due to ego issues.

I wish ED would put out a benchmark integrated with the core engine so we could run valid tests but I know that's not a priority.

I have read through the thread. The guy I was quoting obviously didn't. I don't set core affinity in Windows or Process Lasso and never said anything about doing so. I set a 2 core ratio overclock in BIOS when playing DCS and then Windows and Process Lasso take care of the rest automatically. The guy I was quoting was putting out wrong information about hyperthreading, number of cores, and stability. And Process Lasso works very well for people who don't want to download autoexec.cfg files from random people in a forum.

 

This stuff is complex enough without confusing the issue for new players. In any given chip there will always be cores that can run faster. I have a top 20 score in the world on 3dMark using Process Lasso and am in the 99th percentile of scores on my current rig so I'll go with my own experience and the technical expertise of people who actually know what they are talking about over random people on a forum.

 

The fact remains that DCS does not use more than 2 cores and does not use hyperthreading. Other background and streaming programs might, but not DCS. Not yet anyway. That hasn't changed since this thread started.

 

People are more than capable of using their own judgment, but you need to have correct information to do that.

...get over yourself

ROFL!:megalol:

Yes, DCS doesn't technically "use" more than 2 cores. But it still performs better when given more than 2 cores (and threads) within Windows. And from my own experimenting, it prefers hyper-threading ON for a 10% boost.

I wish ED would put out a benchmark integrated with the core engine so we could run valid tests but I know that's not a priority.

Yes , this is a much-needed feature in DCS . Speaking for myself , certainly , and i think for many , we all spend a lot of time testing/tweaking trying to eke out the best performance from a very demanding sim .

A standard for benchmarking would be of huge benefit for us all , both in terms of sharing results , and in our own standalone tests .

I followed this thread for years, I still have no idea whether or not I would benefit from setting cores? I know this much, I spent many days creating spread sheets to monitor my changes and the results of those changes. As I recall, for my system, I wound up turning Hyper Threading off, and (AT THE TIME) it performed better because it significantly reduced micro stuttering for some reason for me. I have since upgraded my GPU twice, and I never went back to fiddling with Process Lasso. Based on even what I have read here again today, Im not sure its worth my time? BitMaster added his point regarding the Chipset potential factor,,, I dont know if that relates to my system or not as I have a Z170,,, and I have no idea what to read into that or how I would be impacted. Any who,,, good reading,,,

I still have no idea whether or not I would benefit from setting cores?

It really just depends on the chip. Selecting cores is mainly for people who want to load balance for other processes while still maintaining an enjoyable game framerate.

There again is the chip matter,, I really dont even know if it would matter on X170,,, anywho,,, I am starting to dabble into VR, and I wonder the potential impact? Perhaps it would be best to attempt balancing due to the VR needs? I dont know.

I really dont even know if it would matter on X170,,, anywho,,, I am starting to dabble into VR, and I wonder the potential impact? Perhaps it would be best to attempt balancing due to the VR needs? I dont know.

Wouldn't worry about it unless you are trying to do something stressful like streaming. I primarily use core selection to keep DCS off CPU0 and 1.

Nothing stressful other than trying to run my settings all as high as possible. And I also have tried to isolate DCS to cores 2 & 3 myself,,, thanks.

 

Yes, DCS doesn't technically "use" more than 2 cores. But it still performs better when given more than 2 cores (and threads) within Windows. And from my own experimenting, it prefers hyper-threading ON for a 10% boost.

Yes, I already know that, thanks. I don't restrict DCS to 2 or 3 cores. I over clock the 2 best cores in BIOS with the 2 core ratio feature of ASUS BIOS and Windows take care of the rest.

Please post some valid benchmarks and videos showing DCS performing better with your autoexec.cfg and a 10% boost. DCS does not use multithreading. Multithreading is using 2 logical calculation threads within one physical core. DCS does not do that. Hopefully with the Vulkun build it will.

https://en.wikipedia.org/wiki/Multithreading_(computer_architecture)

Test: Setting CPU Affinity

DCS does not use multithreading. Multithreading is using 2 logical calculation threads within one physical core. DCS does not do that.

wat? it doesn’t do that?

how does it prevent it from happening?