Performance changes between Physx4 and Physx5

[zemlifr]

Hello, I have 2 questions that are partially connected.
Recently we have updated our software from Physx 4.1.2 to 5.5.1.
In one of our scenarious, we have noticed worse performance since then.

Our app is using PxDefaultCpuDispatcher with 2 threads.

Scenario is this:

1. There are few static heightfield actors.
2. There is a rigidDynamic laying on heightfield, there are contacts reported
3. Small force is applied to rigidDynamic each frame. Not enough to move it from its place though
4. Actor uses vehicle simulation, we can switch between legacy and new one, both perform basically same.
5. wakeUp is manually called on this rigidDynamic actor regularly.

So far I can see around 10% drop in performance.
It seems that when I remove manual wakeUp call, performance gets better, drop is only around 5%. (And its not because actor goes to sleep, there is force applied that keeps him awake)

Then I tried to play with snippets and used SnippetHelloWorld to measure time needed for simulation using std::chrono::high_resolution_clock

I have changed snippet to contain only stacked boxes without ball hitting them so they all go to sleep soon.

From my measurements, it seems that Physx5 performs around 5-10% worse when there is small number of boxes (e.g. < 1000). while performing much better with large number of actors. At the same time, they perform same when scene is empty, or when I set dispatcher cores to 0,

So my questions are these:

1. Is there anything that could worse performance just by calling wakeUp manually?
2. Is there some change in dispatcher implementation or threading system that could cause this difference (like different task granularity, different synchonization mechanisms used, etc..)

EDIT: I just tried HelloWorld snippet in 5.6.0 where high priority tasks are available and it seems to perform better than 4.1.2. But my questions stay.

[zemlifr]

Ok I think I found answer for decreased performance.
It seems that default broadphase algorithm was changed from ABP to PABP. Switching back to ABP seems to resolve isse in HelloWorld snippet.

However this is not stated in documentation -> #453