The Aonix data on their website was very useful. It proved most of our points. That's why we reference it. Still available through archive.org. Although, just checking, I find a lot of the good links are dead on the times I tried. Uh oh.
In the Aonix design, there is no GC on the hard-real-time threads or portions of the heap. Those are usually done statically anyway for max predictability. The GC can apply to anything else with it preempted by real-time threads when necessary. It was usually tied into a RTOS like LynuxWork's (now Lynx).
I still refer to Aonix, because they were more developer friendly, had more information on their website than the few whitepapers from PTC and the web site is still partially up.
