Pretty amazing stuff here from Adam Leventhal – a few months ago, I was really looking forward to seeing DTrace on OS X: it now sounds like the implementation of DTrace there has missed the point in some fundamental ways.
“Systemic tracing” to me means all of the system, not just the bits the lawyers are happy to let you look at. Here’s hoping the Apple engineers get this sorted out.
[ Disclaimer: I haven’t bought a copy of Leopard yet. I still find it a bit weird that I have to pay for something that includes ZFS and DTrace, when I can get working versions of them for free in my preferred operating system. If my Mac is still supported when 10.6 comes out, I might upgrade to that. For now, 10.4 does everything I need. ]