Djprobe is a new light weight probe that uses 'jmp' instruction instead of 'int3'.
Djprobe provides the non-locking and ultra-light probe function. It uses the relative `jmp` opcode instead of `int3` break opcode. It can reduce overheads of probing by the interruption, single-stepping and locking.
As is well known, it is not assured that both a `jmp` instruction and a destination address are inserted atomically. To avoid this atomic operation problem, djprobe bypasses the section under 'construction' by using kprobes.
The detailed documentation about djprobe is in the README text file included in the source package (tar ball) of djprobe.
The djprobe’s overhead is far smaller than kprobes’ one. I already evaluated the overheads of djprobe and other probes in several situations. The report of the results can be downloaded here.