Multiple obi solvers

[lufydad]

- Maybe you're using async compilation in Burst? This will lazily compile your jobs on the fly the first time they're executed, during gameplay. The result is that the first few frames of anything that uses Burst are a lot slower since A) it's not actually using Burst yet B) code is being compiled in the background as the game runs. This only happens in-editor (standalone is precompiled at build time) and can be optionally disabled so all Burst code is compiled when you press play.

Thanks for the tip about the async compilation, I didn't know it, although I use jobs in other places. It improve the performance a bit, but it doesn't seems to be the heart of the problem.

- Instantiating objects in the solver does have some overhead, as particle data must be converted from actor to solver space and constraint batches from different actors merged. Maybe this extra overhead is enough to tip performance over the edge of the spiral? Does this happen with fewer actors (ropes) in your scene?

With only 3 actors (instead of 12) the problem seems similar : https://imgur.com/a/r2mQwZy. It looks like the death spiral is triggered by the function AddActor of ObiSolver (see https://imgur.com/a/eYkvepv).
Is there a way to improve it ? by changing some parameters for example ?