Linux is suffering from a lack of a good debugging API. There is a decent progress in the kernel debugging and profiling tools, but for userspace no changes were made for a long time.
"ptrace" is the main userspace debugging API, used behind tools like "strace" or "gdb", but it's old and clumsy. Quite new "perf" tool, on the other hand, allows user to get various CPU/Kernel stats mostly useful for profiling. Before "perf" you could only try to emulate your program using "valgrind" to get, say cache misses.
The command "perf trace", seems to move "perf" more into the "ptrace" domain. This is indeed exciting.
"ptrace" is the main userspace debugging API, used behind tools like "strace" or "gdb", but it's old and clumsy. Quite new "perf" tool, on the other hand, allows user to get various CPU/Kernel stats mostly useful for profiling. Before "perf" you could only try to emulate your program using "valgrind" to get, say cache misses.
The command "perf trace", seems to move "perf" more into the "ptrace" domain. This is indeed exciting.