Hi There
I have a Physics test scene that has 100 dominoes which topple in the usual way, this works as expected but the frame rate gets slower as more dominoes fall, I have sleepvel values set quite high and I assumed that once each rbody has come to a rest after falling it would enter sleep mode so at most only a few rbodies would be active at any one time but it seems this isnt happening, is there a step Iam missing?
Thanks
Chris
potentially you have too many drawcalls (you can click on the stats button top right in the unity editor).
But it also depends a bit on the platform you target cause even when sleeping, its still 100 interacting dominos 
Thanks for the reply The camera doesnt change, it has all the dominos in view all the time and the frame rate just steadily drops from 200fps to 60fps as the last tile falls, but then jumps back to 200 as I guess as the whole system is put back to sleep. It isn’t really a great problem as it’s just a test scene but I was just wondering if the problem was due to the rigid bodies not going to sleep properly as they are all stacked on top on one another as they fall.
That is indeed possible that the push through impact is causing this.
You could go ahead and make the system more powerfull by make it kinematic if you know that it has a domino above and below, but you risk lose of dynamical believability. depends a bit on what you want to achieve in detail.
When you think about it, domino’s is a somewhat challenging physics scenario - as each domino applies force/torque to the one behind and in-front of it, and this continually changes as they fall.
Thanks guys, yeah it is a tough situation, guess I will add my own sleep system on top just for fun, not really important to my project was just testing PhysX scenes. Thanks for the help though
Chris