Using HPROF for CPU/Heap profiling
Granted HPROF is a pretty primitive profiling tool, but for what it's worth this recent article provides some details:
HPROF was converted from using JVMPI to JVM TI in Tiger.
The source is available in the Mustang snapshot sources and as part of the Tiger and Mustang JDK binary downloads.
I'd be interested in any features or comments people have on it.