Jump to content

Tips for max CPU/GPU utilization?


NightshineRecorralis

Recommended Posts

So I was playing and testing some SSTOs today, and I happened to have task manager out beside KSP. I noticed that my CPU wasn't really going past 70%, but it seemed like my framerates were dropping due to lack of processing/graphical power. I'm sorta confused as to why that is happening. In my current config, it should be my CPU bottlenecking and not the GPU, but neither are close to 100% utilization. Should I prioritize KSP in task manager? Will that help?

i3-7100

GTX960

8GB DDR4

Link to comment
Share on other sites

KSP has limited multithreading since 1.1: while several threads are used by the physics processing engine, a single craft is bound to a single thread. This means that you can have one thread running at 100% while the other ones are not used at all by the game.

It's the way the game (and Unity itself AFAIK) are coded and I don't think there is any solution to that.

Earlier, there was the trick of forcing OpenGL (or DirectX11, not really sure which does what) to transfer some CPU or RAM load to the GPU but I'm not sure if it still works.

Link to comment
Share on other sites

A lot of this has to do with Unity. Prioritize KSP probably will help a little, but not that much. Separate  gameobjects is what is the likely cause of frame drops. Other than minimizing the parts use use on a ship (i.e. maybe you don't need 20 lights on your space station) try dropping the pixel light count down one or two. It saves both CPU and GPU usage.

Link to comment
Share on other sites

4 hours ago, Curveball Anders said:

Your CPU is dual-core (and HT, so 4 virtual), and the CPU utilization reported is for both cores.

KSP isn't fully multi-threaded so it will not be able to use all cores/threads equally.

 

None of the cores/threads are over 75%

GPU is @100, but it is massively underclocked.

3 hours ago, Ty Tan Tu said:

A lot of this has to do with Unity. Prioritize KSP probably will help a little, but not that much. Separate  gameobjects is what is the likely cause of frame drops. Other than minimizing the parts use use on a ship (i.e. maybe you don't need 20 lights on your space station) try dropping the pixel light count down one or two. It saves both CPU and GPU usage.

 

Been there, done that. Doesn't really help.

Link to comment
Share on other sites

found this..:

it will only be one thread per vessel. Basically when you are approaching your space station your craft and space station are in different threads (and your OS might put these threads into different cores if it sees it worthwhile). But once you dock, they get merged into one thread and to one core.

If you are trying to dock big ship to big station, it should help with FPS, but once you are docked it will basically be the same situation as now.

Hope this help a little with understanding how kerbal uses "cores".

Link to comment
Share on other sites

Utilization of either CPU or GPU is a red herring unless fps drops less than 60 (or the maximum your monitor can display and you can perceive).  If your framerate drops into the "hey! I can see a framerate issue!" then it probably (for KSP) is a CPU (physics engine) issue (and your GPU can simply loaf along and attempt to conserve power while drawing all the frames it gets).  Also, it would probably take at least 4 (and more likely some multiple of 4) separate equally large ships all within physics range to make sure all available CPUs (and threads) were processing data.

In other words, KSP just isn't going to "efficiently" use all CPU time or GPU time.  That type of thing is typical only in consoles (where everybody has the exact same CPU and GPU) and even there isn't likely to work with console-KSP since each space craft is custom designed by the user (and not a developer carefully balance CPU & GPU power).  So don't worry about it.  Now if you are trying to optimize your system to crank up the graphic options and resolution, or trying to keep KSP working while you make supersized rockets, that is another issue (that is unlikely to be solved by "balancing" or "hitting 100% utilization" CPU & GPU usage).

Link to comment
Share on other sites

KSP requires very little GPU, but a lot of CPU. I upgraded from hd5850 to r9 280, and got almost no change in fps. But when I went from athlon II x4 to xeon x5600, the increase was noticeable. Its very true that IPC (memory access) speed and power of thread processing by cpu core per clock are more helping than amount of cores, their speed or multicore task distribution efficiency.

There are few eaters of CPU performance, most prominent are aerodynamic fx effects - I always set them to very low. Terrain quality eats quite a lot, can easy set it to Low. Physics delta frame still plays a role, whilst doing same calculations regardless, setting it to lesser value will give more time to fps redraw, and less time to physics update. Also, all fairings eat a LOT of CPU, reduce them where possible. 20 fairings for example totally destroy my fps, where I can have 2500 barrels of fuel on screen no problem.

Finally, the FPS graph itself when open eats around 20% of fps...

Edited by Kerbal101
Link to comment
Share on other sites

  • 10 months later...

I can personally attest to quite large performance improvements from overclocking. I'm currently running the game on a 4670k @4.7-4.9 ghz (depending on the ambient temperature, due to unique conditions such as occasionally poor ventilation) with  DDR3 2166 mhz and very tight timings. Granted overclocking can be very easy or very difficult. For more information on this topic there are countless forums, such as tom's hardware or overclock.net. If anyone reading this is willing to try overclocking, provided your equipment supports it, it can yield quite significant improvements. One little detail to keep in mind however, is that KSP heavily favors single threaded performance so sometimes it can be a good idea to use a separate overclocking profile for KSP which has one or two cores clocked higher than the rest. This allows for increasingly higher multipliers while still staying within reasonable temperatures and voltages, but can also lead to an unstable system, if done incorrectly.

<This is meant as an informative post and is not meant to spark further conversation>

Link to comment
Share on other sites

This thread is quite old. Please consider starting a new thread rather than reviving this one.

Join the conversation

You can post now and register later. If you have an account, sign in now to post with your account.
Note: Your post will require moderator approval before it will be visible.

Guest
Reply to this topic...

×   Pasted as rich text.   Paste as plain text instead

  Only 75 emoji are allowed.

×   Your link has been automatically embedded.   Display as a link instead

×   Your previous content has been restored.   Clear editor

×   You cannot paste images directly. Upload or insert images from URL.

×
×
  • Create New...