The goal of the project is now to develop a user library called libpfm4 to help setup performance events for use with the perf_events Linux kernel interface. The development of the perfmon kernel subsystem, libpfm and pfmon has now stopped.
OProfile is a low-overhead, transparent profiler for Linux, capable of instruction-grain profiling of all processes, shared libraries, the kernel and device drivers, via the hardware performance counters.
Function call tracing in the Linux kernel and userspace applications. Dynamically sets probes (using VProbes, a KProbes variant) and displays the function call trace of a process calling kernel or application functions. The superior of strace and ltrace.
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.