BTW I looked around a bit and found another similar system, based on QEMU instead of Valgrind, claiming to be faster, ie less runtime overhead while tracing, an

BTW I looked around a bit and found another similar system, based on QEMU instead of Valgrind, claiming to be faster, ie less runtime overhead while tracing, and also supporting kernel mode: http://wiki.nss.cs.ubc.ca/Tralfamadore http://wiki.nss.cs.ubc.ca/Tralfamadore Edit: never mind, the program does not seem to be publicly available, just papers