Physics lag issues, syncing issues, mp

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Bixkitts
Posts: 3
Joined: 02 Jan 2018, 02:14

Physics lag issues, syncing issues, mp

Post by Bixkitts » 02 Jan 2018, 02:41

A friend and I are playing openmw multiplayer over LAN, I'm hosting a server. We were running around happily for many hours when my game shed any and all semblance of a playable framerate (2-4 fps from a usual 20-30 in a town). After looking at the performance monitor it was clearly the physics screwing me over at 200-300 ms. It's only like this around Ald Ruhn's exterior, probably some object or npc glitching out around the silt strider part of town. It works fine everywhere else. My friend however has no issues. It is for all intents and purposes unmodded. (run faster.esp and optimised meshes which I tried uninstalling to fix the issue unsuccessfully)
I looked around at the physics meshes with a console and didn't see anything overtly upsetting.
Wondering how I can reset the Ald Ruhn cell or something to kick over this hurdle on my path to enjoyment.
On top of that, containers don't get synced between me and my friend 90% of the time. They only sync when someone reconnects, or when the game feels like it.
Finally, I'm new to openmw and wondering when the next release can be expected, I haven't been around long enough to guesstimate development times. Synced enchantments and stuff sounds exciting!

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AnyOldName3
Posts: 618
Joined: 26 Nov 2015, 03:25

Re: Physics lag issues, syncing issues, mp

Post by AnyOldName3 » 02 Jan 2018, 02:55

Anything to do with multiplayer is actually TES3MP, not OpenMW, although it is based on OpenMW code (as you can do that with open source things). We might merge their work into OpenMW eventually, but for now, you should probably stick to the TES3MP forum subsection and the TES3MP discord server for support.

The physics issue is potentially at our end, though, so you might well get some help with that in this thread.
AnyOldName3, Master of Shadows

Bixkitts
Posts: 3
Joined: 02 Jan 2018, 02:14

Re: Physics lag issues, syncing issues, mp

Post by Bixkitts » 02 Jan 2018, 03:09

In my tired rage I forgot the two things are separate- apologies... disregard the multiplayer aspect, the outstanding issue is the physics lag bug I would love information about that!

CMAugust
Posts: 76
Joined: 10 Jan 2016, 00:13

Re: Physics lag issues, syncing issues, mp

Post by CMAugust » 02 Jan 2018, 05:02

OpenMW is currently programmed to update physics in fixed time steps, exactly 60 times a second. This ensures maximum stability and accuracy in the physics simulation no matter what the player's frame rate is. However, if the PC can't maintain 60fps during gameplay (due to weaker hardware, performance-heavy mods, etc.), the physics thread has to work harder to account for the frames that were missed, which may cause the frame rate to spiral ever downwards. I've never had this happen on my machine, but can somewhat see the effect by artificially limiting the frame rate in settings.cfg.

If your average is 20-30fps in towns, I suggest turning off the water shader (if it's on) and seeing if that improves the average frame rate enough to potentially prevent a "spiral".

raven
Posts: 49
Joined: 26 May 2016, 09:54

Re: Physics lag issues, syncing issues, mp

Post by raven » 02 Jan 2018, 12:01

There is an environment variable OPENMW_PHYSICS_FPS which might be worth trying as a workaround.

Default is 60. You could try something lower and see if you still hit the spiral of death.

Bixkitts
Posts: 3
Joined: 02 Jan 2018, 02:14

Re: Physics lag issues, syncing issues, mp

Post by Bixkitts » 02 Jan 2018, 14:32

Right, the "ResetActors" console command got rid of the lag by moving all the NPCs in the cell back to their rightful positions.
I don't know how to modify environment variables and can't find anything about it at the moment. But thanks!

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