Stutter/freeze when entering and then leaving/increasing timewarp

[stellaruniversex]

After entering (non-physics) timewarp, and then either increasing timewarp once (doesn't happen with further timewarp increases), or leaving timewarp and returning to normal speed, the game stutters/freezes for a short period; the period of time that the game freezes when this happens seems to be proportional to number of engines/parts on ship (regardless of whether of not they have Background Thrust enabled).

Version 1.12.5 (can provide mod list if needed)

[Phantomical]

When entering and leaving timewarp background thrust has to create a bunch of part resources for the warp buffer. That's the cause of the stuttering you're seeing. There's likely something I can do to improve things though. I'll take a look when I get a chance.

Worst case I can make this a one-time thing so that you only get the stutter once instead of every time you enter/leave time warp.