I have been using the beta release of 9.0 with a number of flex modules (10-15). It runs any where from 5-15min and then completely hangs and has to be killed. I did see the other thread on Mac issues, but this seemed a little different as there is 0-1% cpu usage, it is just waiting as the dump suggests. I have tried it w/ both Perforce enabled/disabled. I attached a thread dump.
I am using:
java version "1.6.0_15"
Java(TM) SE Runtime Environment (build 1.6.0_15-b03-219)
Java HotSpot(TM) 64-Bit Server VM (build 14.1-b02-90, mixed mode)
I have been using options of: -Xmx -Xms32m -Xmx756m -XX:MaxPermSize=256m -server -ea -Xbootclasspath/a:../lib/boot.jar