TimeDoctor is a tool to visualize execution traces of tasks, queues, cache behavior, etc. While originally targeting embedded media processors and includes specific features for analyzing audio/video streaming applications it has wider applicability.
Kernel Analyzer is tool for Linux that monitor task preemptions and interruptions in the Linux Kernel.
Basically it is a Kernel Patch, that comes also with a user proc interface, a KDB interface, and a Java GUI to display charts.