On Fri, Jan 11, 2008 at 06:23:14PM -0800, Roman Shaposhnik wrote: > > I guess we are talking about two different kinds of generality here. > What I have in mind is the generality that would allow DTrace to be > able to offload some of the heavylifting to the userspace. I DO > understand the ramifications of that and I know full well that pushing > DTrace into userspace might be perceived as the deviation from the > original design. To some extent it might even reduce the generality > that you seem to be referring to. >
The issue is not one of design, but of the constraints on the problem. DTrace actions must be executed in probe context. Heavy lifting can be done via post-processing in userland (symbol translation, system() actions, etc), but the data gathering must be done in arbitrary context. How would you call arbitrary userspace code from, say, an interrupt handler? - Eric -- Eric Schrock, FishWorks http://blogs.sun.com/eschrock
