[4.10 beta] Performance issues around Asteroids, that improve on reloading

[LameFox]

For some reason the worst performance I ever see in this game takes place in asteroid fields. But strangely, it comes and goes. Sometimes I will just be flying in an asteroid field and my fps will go down to about ~20 and the game gets very hard to play. Other times, in the same field, doing the same things, it might be more like ~60, whereas outside the field it could be more like 70-90.

Today when this happened during combat in Heretic's End it got so hard to fly with the poor performance that I loaded an earlier save, meaning to fly outside the field and fight there. But when it loaded, my performance went back up. I decided to fly around mining crystals for a while, and after a bit it dropped to ~35 fps. Even when I stopped moving and didn't look around it would just sit at that. I notice that during this time, my CPU is not under heavy load. Not even a single core is at 100%, but my GPU was doing a lot. I made a quicksave and loaded again. Back up to ~65 fps. I spun the ship around for a bit looking at all the asteroids, and it stayed around 55-60. Flying around and mining crystals, it's still roughly 55. Been doing it for a while now and it hasn't recurred.

This doesn't seem to be something I can reproduce reliably or capture with a save, but I felt it's worth mentioning since knowing that it goes away when I reload (and doesn't necessarily come back) is the only breakthrough I've ever had with it. This has been ongoing since release for me, on my current system with an RX 6900XT and a previous one with a GTX 1070ti. It doesn't seem to depend on which field, in what sector, or have anything to do with other ships being around. Just a lot of asteroids and chance.

I am playing on mostly max settings, with no vsync, shadows set to 'normal' manually, and 4x MSAA—but I've tried every type of AA, even turning it off altogether.


dxdiag
vulkaninfo

[spookywatcher]

You are correct. I've noticed the same behaviour. Even a game restart will get the FPS up too. It's like some background equation gets stuck and really gimps the perf. Reload and bam...smooth fps again. The drop is not reproducible (since a reload fixes it) but the increase is. It'll happen to me even in the first minute of a game sometimes. Just reload the same save and bam fixed.

So You're not alone for sure.

[LameFox]

Another observation:

I was flying along that really long straight stretch of asteroids in Nopileos' Fortune II today and I noticed that, in travel mode, my fps would hover around 80-90 as I went, but then every so often it would slow to something horrible like 2 fps, creep back up to 90, sit there for a while, and then plummet back to almost nothing. It did this in what felt like steady increments, as if it was related to moving between regions of the map. I forget what the technical term for those is. To test this, I hit the brakes when I reached one of these fps drops, turned around, and flew back out of travel mode. It seemed to recur in the same place, and then slowly recover as usual. I turned around again and it recurred after a very short distance.

I do not know if this is exactly the same issue, because it recovers over time, but I think it is similarly something that only happens in asteroid fields. Maybe just the sheer number of things loading into existence when crossing from one chunk of space to another. The interesting thing is that the times when my performance does not recover seem to start a lot like this. I do not know if the barrier between chunks is directly visible to the player at all but I'll try to keep this in mind next time I get a permanent drop and see if returning to the same area after loading causes a temporary drop that might indicate one.

[BaronVerde]

@LameFox, your graphics card should render X4 with lightning speed (I want it ).

Just to be sure that those clients (Steam, GOG) don't slide in layers that affect performace: can you and have you tried starting X4 without the clients and without all those vulkan layers that, judging by their names, appear to do logging, caching, etc, ...

Vulkan layers "hook into" the API's function calls, which can under circumstances heavily affect performance. Just as an example, the regular khronos validation layer, a helper for programming, that prints out errors and warnings can drag the performance down into the abyss if it logs an error multiple times a frame.

I would definitely try to start X4 stand-alone, if possible, and if it is only to reduce complexity for a moment and rule out that those layers interfere too heavily, in which case one can get back to using the gog/steam-clients.

[LameFox]

I could try the nosteam exe at some point, but how do I turn off the vulkan stuff? Not really familiar with it.

edit: seems like I'll have to wait as I'm in the beta, the exe isn't for that version.

[BaronVerde]

The no-steam exe should do it.

I confess that I have no idea about the Windows OS and can't help on the side.

One thing, because this is how layers are activated from the environment: you could check if the VK_INSTANCE_LAYERS environment variable exists and lists any of those layers from the vulkaninfo output. If it does, set it to empty for the test with the no-steam executable, or delete the vriable. There may also be a 'vk_layer_settings.txt' file somewhere one could temporarily rename.

Sorry for not being more helpful with technical details, I did a bit of dabbling with the Vulkan API, but from my perspective one would activate layers from inside of the application. Since I have no clients running (am on Linux anyway) I am not confronted with additional layers.

[Alan Phipps]

If you want further technical discussion about the likely impact of layers etc then look here and onwards.